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Ran my poor mans compression test today using a piston gauge. I posted to the FB group and got the collective feedback there but I know that not everyone up there knows what they are talking about since on person told me I had a leaky gauge because the readings were bouncing...haha
One rotor shows 60/60/30 and the other shows 60/60/60. This is a cold engine since using only the starter to turn the motor. Someone on FB said the 60/60/30 indicates it's a side deal that is either bad or stuck. Some people say put ATF in while others say ATF is a bad idea; they suggest Marvels Mystery Oil. I know you need a warm engine for a true test and this is more to see if there any problems, which there appear to be in at least one rotor.
So I suspected that the compression gauge I had wasn't working right because the schrader valve, which I didn't remove, looked jacked up. I went and got a new gauge today, removed the valve, and ran the compression tests again from the trailing plugs. I hit approx 90/90/90 for each rotor! I also pulled the plugs to see if they would fire, which they did. I don't know how good or bad because this my first go round doing this.
I got excited and posted to the RX7 Facebook group and the collective suggested I try to start her. There were varying opinions on how to do this (ATF, Starting Fluid, gas). I decided to put the current fuel pump setup back in, add 1/2 gallon of gas and just give it a shot (with a fire extinguisher handy).
The damn thing fired up! She sounded rough (someone suggested the plugs were probably terrible), but she ran for a minute or so! I didn't touch the throttle, just let her idle. The turbo inlet did't spin at all. My buddy, who's a gear head, albeit with piston engines, said the turbo not spinning at all could be adding some back pressure that is causing the weird idle. He thinks that I'm better off with the rebuilt Streetport from Rotorsports vs. trying anymore to salvage this. He looked in the radiator cap and it looked like mud in there. I probably should have flushed the coolant system first so who knows what sludge is in the engine. He isn't a rotary guy so maybe I shouldn't be as worried. The plan before was to replace the engine because new seals installed would have been about $2300 and a rebuilt street port was $3600 with a core swap.
Not sure what my next step should be at this point. He suggested I take everything out of the engine bay, get the core support replaced since there is rust near some of the welds that are clearly not factory and on the broken metal (that is brittle) near the driver side headlight, and have the engine bay sand blasted and painted black. He suggests structural first, then mechanical, then aesthetics. Being my first project car ever, I'm lost on which way to go because everyone has a different opinion but I don't know what I don't know. What I do know is what she fired up today, I felt like a million bucks! Here are the vids of the test and her running.
Just take the motor out and tear it down. If it's no good then buy another. If it's good then rebuild.
Also, it doesn't matter if someone is a piston or rotor person. Flushing coolant is flushing coolant. It's not rocket science.
+1
That engine does not sound salvable as a block. How committed are you to this particular car? It's best suited to be stripped, caged, and raced by someone who's done that a couple dozen times. There's not a lot of stuff to save or keep, aside from the chassis. You wouldn't do poorly to strip all the parts off of it, sell it as a shell, sell whatever parts you can, and invest that money in an FD with better bones.
If you want a ship in a bottle, you've found it. I personally didn't have the stomach, patience, or time economy for it.
That engine does not sound salvable as a block. How committed are you to this particular car? It's best suited to be stripped, caged, and raced by someone who's done that a couple dozen times. There's not a lot of stuff to save or keep, aside from the chassis. You wouldn't do poorly to strip all the parts off of it, sell it as a shell, sell whatever parts you can, and invest that money in an FD with better bones.
If you want a ship in a bottle, you've found it. I personally didn't have the stomach, patience, or time economy for it.
curious, what specifically doesn’t sound right? Being a full bridge port, I don’t know what a “healthy” one sounds like.
As for commiment, when I found this, the goal was to make her project car and get her back to good shape and keep the car as a weekend/occasional track car. I knew it would take time, patience, and money. How much I wasn’t sure of. Now that I got up closer, it’s clear it needs lots of external bits while the interior is in good condition. I wasn’t intending to flip or make money.
Ill admit that I’m impatient and I’m half tempted to just drop the car off with Rotorsports racing and tell them to fix it and send me the bill. At the same time, the point of a project car (to me) is to take time and learn a lot by stripping the car down and putting it back together. The only part I’m hesitant to work on is the motor. There is a wealth of information here and on the inter webs but I’m not sure if it it’s just easier to buy a “new” motor and have that be one less thing to worry about. Also, a full bridge has me nervous about overall reliability.
You guys are nuts, the guy probably got this FD for less than 5k considering it was a family deal that needed work and had been sitting for a while.
You are WAY ahead of the curve right now, since the engine runs and the interior is clean you can probably get 6-8K for it easily.
This is the perfect project car, the body is pretty decent and most of the hard work has been done. It just needs some cleaning up and going through. JohnnyK just had the core support replaced in FD build thread a few months ago, total cost was only a few grand. You got a lot more work to do before the car even leaves the garage under its own power, focus on that first.
As far as bridge port reliability, it will last the same amount of time a brand new motor would when you try to run too much boost and detonate it. Use the motor and turbo set up thats in the car now and see how you like it and adjust to the rotary learning curve.
The motor sounds ok, did you put the fuel pumps back in it to start it? or did you just put gas in the intake?
You guys are nuts, the guy probably got this FD for less than 5k considering it was a family deal that needed work and had been sitting for a while.
You are WAY ahead of the curve right now, since the engine runs and the interior is clean you can probably get 6-8K for it easily.
This is the perfect project car, the body is pretty decent and most of the hard work has been done. It just needs some cleaning up and going through. JohnnyK just had the core support replaced in FD build thread a few months ago, total cost was only a few grand. You got a lot more work to do before the car even leaves the garage under its own power, focus on that first.
As far as bridge port reliability, it will last the same amount of time a brand new motor would when you try to run too much boost and detonate it. Use the motor and turbo set up thats in the car now and see how you like it and adjust to the rotary learning curve.
The motor sounds ok, did you put the fuel pumps back in it to start it? or did you just put gas in the intake?
You are pretty spot on in terms of what I paid for the car. I'll ping JohnnyK on his core support. I definitely need that replaced. I put the old fuel pumps back in. I tested them out and they both still ran so I figured 1/2 gallon of gas in the tank wouldn't hurt her much more than sitting for 5 years. I had fire extinguisher handy just in case things went sideways.
The turbo wouldn't even spin. It didn't even budge so I know I'll probably need a new turbo. I'm also trying to determine who made it, the intercooler, and the radiator. There are no markings on it any of those parts. The previous owner said he handed a bunch of money to Ray @ PF Supercars in VA and they did all the work. My understanding is they are no longer in business but when they were, they "supposedly" had a great reputation for building solid cars. I did some searching here and it looks like the had a fiery death with lots of unhappy customers towards the end so I have no idea where this car fell in the PF Supercars history ...the good or bad end of it. What I do know is that between people saying my turbo isn't a Borg Warner and the lack of identifying marks/brands on the radiator and intercooler, I'm now wondering if the previous owner gave them money and they ordered knockoff parts and pocketed the rest...
curious, what specifically doesn’t sound right? Being a full bridge port, I don’t know what a “healthy” one sounds like.
As for commiment, when I found this, the goal was to make her project car and get her back to good shape and keep the car as a weekend/occasional track car. I knew it would take time, patience, and money. How much I wasn’t sure of. Now that I got up closer, it’s clear it needs lots of external bits while the interior is in good condition. I wasn’t intending to flip or make money.
Ill admit that I’m impatient and I’m half tempted to just drop the car off with Rotorsports racing and tell them to fix it and send me the bill. At the same time, the point of a project car (to me) is to take time and learn a lot by stripping the car down and putting it back together. The only part I’m hesitant to work on is the motor. There is a wealth of information here and on the inter webs but I’m not sure if it it’s just easier to buy a “new” motor and have that be one less thing to worry about. Also, a full bridge has me nervous about overall reliability.
It kinda sounds like a bag of hammers in the video. And, the power pulses are missing. What did the spark plugs look like? You can pull the exhaust manifold off and check the internal appearance of the motor to some extent. You can rotate the engine to inspect all the apex seals. Bore scopes are key. If you see rust in there, it's bad news.
Did you dump any sort of oil in it before starting? There are lots of stories about oil starting race-worn NA rotaries, but you might've just tipped over some FD guys in shock to oil start a barn find fd. If you can hang your fingernail on internal surface scratches, you're supposed to junk the part. So proper oiling and a lack of internal debris is paramount.
If the turbo is seized, the other bearings are also suspect. And, it looks like the engine has been rained on. Vented hoods are for cars that don't see weather....
The car has red flags. For instance, that fuel pump setup was never-OK. You're gonna have to undo weird stuff you don't even understand is messed up yet. No green horn could be expected to know. It makes more sense for a seasoned vet with no learning curve.
The learning curve combined with the distance the car has to go are probably not worth your decade. If you gotta strip and paint the car, you'd probably be better off buying a clean roller. Dropping the car off at a mechanic is going to quickly erase any financial surplus in the project. Rotorsports does good work and it's not a bad idea to get their opinion and a quote, for your reference.
I'm glad you got a screaming deal on an FD. There exists an economy where you can parlay this into a more winnable scenario. Some seasoned vet could strip dip and cage this thing into a winner. This is also probably a good LSx swap candidate (ducks and leaves).
New motors go for about $4500, for now, when you can get them. But, you'll need to dress out the block with stuff, so pencil in a couple extra thousand.
If you're getting 90 psi with consistent pulses, it's worn, but should run. You'll eventually need a rebuild or replace, but you might get some more miles out it before you have to rebuild/replace. That said, you are at a good spot for doing it now vs later after everything is buttoned back up
It kinda sounds like a bag of hammers in the video. And, the power pulses are missing. What did the spark plugs look like? You can pull the exhaust manifold off and check the internal appearance of the motor to some extent. You can rotate the engine to inspect all the apex seals. Bore scopes are key. If you see rust in there, it's bad news.
Did you dump any sort of oil in it before starting? There are lots of stories about oil starting race-worn NA rotaries, but you might've just tipped over some FD guys in shock to oil start a barn find fd. If you can hang your fingernail on internal surface scratches, you're supposed to junk the part. So proper oiling and a lack of internal debris is paramount.
If the turbo is seized, the other bearings are also suspect. And, it looks like the engine has been rained on. Vented hoods are for cars that don't see weather....
The car has red flags. For instance, that fuel pump setup was never-OK. You're gonna have to undo weird stuff you don't even understand is messed up yet. No green horn could be expected to know. It makes more sense for a seasoned vet with no learning curve.
The learning curve combined with the distance the car has to go are probably not worth your decade. If you gotta strip and paint the car, you'd probably be better off buying a clean roller. Dropping the car off at a mechanic is going to quickly erase any financial surplus in the project. Rotorsports does good work and it's not a bad idea to get their opinion and a quote, for your reference.
I'm glad you got a screaming deal on an FD. There exists an economy where you can parlay this into a more winnable scenario. Some seasoned vet could strip dip and cage this thing into a winner. This is also probably a good LSx swap candidate (ducks and leaves).
New motors go for about $4500, for now, when you can get them. But, you'll need to dress out the block with stuff, so pencil in a couple extra thousand.
I pulled the plugs and they made spark (blue) so I figured I'd try them because I wasn't even sure she'd start before I bought some sacrificial plugs. I honestly don't know how good or bad they should look so much as do they spark or not. I just took some pics below. Tell me what you think of them. I did not put any oil into the engine directly (like via the throttle body/intake or spark plug holes). I did change the oil to get whatever crap was in there out (and it was chocolate syrup black).
At first, it was suggested on the RX7 Facebook group to put ATF in since my first compression test showed 60/60/30 which a few people said is a probably stuck side seal. I didn't do that since it sounds like there is quite a debate on whether ATF is good or bad. I was going to put MMO in but I wanted to run a compression test with another gauge. When I got 90/90/90, which is supposedly good for a cold engine, it was suggested to just start her up.
Rotorsports has a rebuilt street port for $3600 + a core swap. I was leaning towards that route but I'm going probably take her over there in a few weeks and let them do a full inspection and write up on what she needs. My "original" plan was to have Rotorsports put their rebuilt street port in, upgrade/replace/repair the fuel system, put a transmission in (3rd gear on this car is toast according to previous owner), and tune it. I think that covers the major mechanical stuff. The rest of the aesthetic stuff I would do over time. Now I am debating if this motor is OK to run with and use money I would have spent on a motor towards a new turbo which I know it needs.
This car was bought for "cheap" to be a project car. While I like the FD, I'm not so in love that I have to have an FD, but if I'm going to spend time and money to fix up a car, I'd rather not have a car you see every day or one I can go to auto trader and find any day of the week. Let's just say if this car costs me $15k to get running (so I'd be all in for $20k) or I could go buy a ready to go car for $20-24k, I'd still rather do it this way. Not because I want to save money, but because the journey (and torment) to get her running, is half the "fun".
That being said, I don't know what I don't know and had Bryan @ Rotorsports not told me this was a pretty good deal (based on photos) for a car with 45k miles and a clean interior, I'm not sure I would have pulled the trigger. I did some searching and when I saw what people where paying for rollers with no interior or engine, I figured this was worth a shot. Worst case, I could dump it and probably break even or I could part her out and probably make some money. Thankfully, I'm in a situation where I could throw money at it if I wanted to but I'd rather make smart decisions about what I do, what it costs, and what it needs vs. just handing money to a mechanic and getting a turnkey car back in return. I would love for it to drive ASAP, but if it takes me a year of chipping away at, I can live with that.
I dropped her off yesterday with Bryan @ Rotorsports Racing. I'm having Bryan do a full inspection and write up of what the car needs vs. what can wait. My perfectionist self literally wants to replace every part that has even the slightest rust on it. Having a pro evaluate it and give me a list should help be budget and plan.
Bryan turned her on an she ran for a few seconds and stalled out. He picked up the Apexi controller, pushed a few buttons, and she ran and he drove her right into his garage. He said he upped the fuel level and that seems to keep her going. He was amazed at how easily she started and thinks I've got a good motor still. He is going to drop the engine and tranny and inspect the engine, do a compression test, and send the the turbo off to a local shop that will inspect it for free and let me know if it's worth a rebuilt or if I should just get a new turbo. Odds are high, it's toast.
He said the motor sounded pretty spot on for a full bridge, so the "bag of hammers" sound that @Narfle stated above is pretty normal. And my phone is ringing and it's Bryan....
So...Bryan said the transmission fluid has been drained and all sorts of stuff came out. He said it looked like something exploded in there (we knew 3rd gear was toast). Since I'm putting a new one in, I guess it doesn't matter. He also said the custom carbon fiber driveshaft was bolted on in a way that made getting off virtually impossible. He warned me it may not go back on because they had to get creative to even get it off. We also identified the Radiator as being a Fluidyne which he said is a good radiator. Once he gets the motor off and inspects it, we can decide if it's worth having him take it a apart for a full internal inspection.
After some thought, if this engine is good, I may just replace the turbo and run this one vs. putting a new or rebuilt in. Bryan did say if the engine is good, it's probably worth $2-2.5k to the right buyer so I could offset the cost of a new one. The issue is we don't have a build sheet on it but it may be worth it for me to pay him anyways to tear it down and inspect it so he can document what he finds.
As always, open to thoughts/suggestions/comments...
I dropped her off yesterday with Bryan @ Rotorsports Racing. I'm having Bryan do a full inspection and write up of what the car needs vs. what can wait. My perfectionist self literally wants to replace every part that has even the slightest rust on it. Having a pro evaluate it and give me a list should help be budget and plan.
Bryan turned her on an she ran for a few seconds and stalled out. He picked up the Apexi controller, pushed a few buttons, and she ran and he drove her right into his garage. He said he upped the fuel level and that seems to keep her going. He was amazed at how easily she started and thinks I've got a good motor still. He is going to drop the engine and tranny and inspect the engine, do a compression test, and send the the turbo off to a local shop that will inspect it for free and let me know if it's worth a rebuilt or if I should just get a new turbo. Odds are high, it's toast.
He said the motor sounded pretty spot on for a full bridge, so the "bag of hammers" sound that @Narfle stated above is pretty normal. And my phone is ringing and it's Bryan....
So...Bryan said the transmission fluid has been drained and all sorts of stuff came out. He said it looked like something exploded in there (we knew 3rd gear was toast). Since I'm putting a new one in, I guess it doesn't matter. He also said the custom carbon fiber driveshaft was bolted on in a way that made getting off virtually impossible. He warned me it may not go back on because they had to get creative to even get it off. We also identified the Radiator as being a Fluidyne which he said is a good radiator. Once he gets the motor off and inspects it, we can decide if it's worth having him take it a apart for a full internal inspection.
After some thought, if this engine is good, I may just replace the turbo and run this one vs. putting a new or rebuilt in. Bryan did say if the engine is good, it's probably worth $2-2.5k to the right buyer so I could offset the cost of a new one. The issue is we don't have a build sheet on it but it may be worth it for me to pay him anyways to tear it down and inspect it so he can document what he finds.
As always, open to thoughts/suggestions/comments...
Awesome, I am glad you took it to a rotary shop instead of listening to some of the people in here and just throwing money at the car. Your going to need that new motor money to do a few updates like the turbo and fuel system along with the front end stuff your wanting to do.
Honestly, a few thousand $$$ spent with Rotorsports to get the car back to into shape will have you a running and driving car THEN you can focus on the front end/head lights.
Awesome, I am glad you took it to a rotary shop instead of listening to some of the people in here and just throwing money at the car. Your going to need that new motor money to do a few updates like the turbo and fuel system along with the front end stuff your wanting to do.
Honestly, a few thousand $$$ spent with Rotorsports to get the car back to into shape will have you a running and driving car THEN you can focus on the front end/head lights.
Now the big question is what turbo to get? I'm looking for 400-450 WHP. Bryan really likes the Borg EFR 8374 because they spool up so quick but I think it's a bit overkill ...and it's like $2400 for the turbo alone...
Now the big question is what turbo to get? I'm looking for 400-450 WHP. Bryan really likes the Borg EFR 8374 because they spool up so quick but I think it's a bit overkill ...and it's like $2400 for the turbo alone...
EFR stuff is definitely good stuff, and you will be happy with the response and power it makes, but it comes at that higher price tag.
Just tell him that you want the SXE version, which has similar inconel and billet wheels but not the ball bearings. You will be giving up 500+ rpm of spool, but they are well under $1k at around the $800 mark. You might even be able to use the hot side that you have now, you would just need to confirm with Bryan.
So I got the initial (verbal) report back from Bryan @ Rotorsports Racing.
Engine: Front rotor was making decent compression but the rear rotor has three blow corner seals. Bryan was pretty amazed it ran and didn't blow an apex seal and scratch the hell out of the housing. Engine does have a full bridge and is also dowell pinned. At this point, the cost for him to rebuild this motor is only about $500 less (with core swap) than getting one of the rebuilt street port motors he has (with 3mm seals). At this point, it seems like a no brainer to go with a rebuilt vs rebuilding this one. He says the housing are in decent shape but being dowell pinned is going to make parting it out hard for me if I decide to not core swap it. He's going to take some measurements tomorrow to give me more details on the condition. He says just eyeballing it, the housings have some step wear but the rotors and shaft appear to be in decent shape.
Clutch: the ACT 6 Puck clutch in there has a cracked disc. I'll probably have him replace this since he's got everything out already
Transmission: As mentioned above, 3rd gear is toast. He sent me a photo of what came out of it
Turbo: out at his turbo guy for a free inspection, but initially it appears to be a cheap knockoff of Borg Warner SX series. Oil line to the turbo was busted. I'm leaning towards a BW SXE anyways
Fuel System: They have a fuel hanger I could buy or they can rig the one I have back to single pump setup. I need a new pump for sure. They suggest Denso but I think I'm going Walbro to save some cash. Also need a new fuel regulator
Here are photos he texted me. More detailed write up from him is coming in the next day or two
This is the report I got back from Rotorsports along with photos of the clutch and the compression numbers:
"The engine had 3 additional dowel pins installed, this requires machining of the engine rotor housings and the three side housings in order to install the dowel pins, additionally 2 of the dowel pins were shortened to allow fitment.
All three side housings wre bridgeported- the porting appears to be well done- (I'd have left the "bridge" a bit wider to give more support to the corner seals)
All side housings showed some normal "step wear" near the spark plugs. This is normal.
Rotor Housings have some wear-but not very bad, they measured within factory specs for shrinkage (usually the aluminum housings will shrink near the sparkplugs.
They have some striations on the contact surface where the apex seals ride- usually a sign of not enough lubrication from the OMP.
All apex seals were still intact, & showed normal wear- the apex seal springs were not flattened
Three corner seals were shattered on the rear side of the rear engine rotor. Fortunately they were still in place and did not gouge the rotor or rotor housings- Very Unusual!
Engine Rotors do not have contact markings or damaged apex seal grooves- All rotor seals,springs, exhibit wear & should be replaced- Oil control seals, springs & 0-rings also show wear & should be replaced.
The coolant level sensor (located in the thermostat housing) will also need replacement- a new waterpump & thermostat is also recommended."
This post is fascinating. I admire all the work you've done already. I stumbled upon your original other thread and then came to read this one.
I'm not used with that, but I'm wowed by all those broken corner seals still in place, what a luck !
All the best for the rebuilt and making this FD on road again soon !
This post is fascinating. I admire all the work you've done already. I stumbled upon your original other thread and then came to read this one.
I'm not used with that, but I'm wowed by all those broken corner seals still in place, what a luck !
All the best for the rebuilt and making this FD on road again soon !
Thanks! It’s been interesting and it’s about to get more expensive. I’m glad I took it to an expert vs. trying to troubleshoot my way through everything and probably making it worse or more expensive down the road. I would have probably tried to drive it not knowing I had bad corner seals. When it comes to the fuel system and the engine, I’m going to let an expert do it.
I’m going to move forward with replacing this engine with one of Bryan @ Rotorsports Racing’s custom streetport engines (3mm Mazda seals) vs trying to rebuild this one. The price difference is neglible. I’m not sure if I’ll core swap or keep my core. Given than it’s pinned, it’s pretty much impossible to sell the rotor housings separate and I’m not sure I can get much more selling the engine in pieces vs the core swap savings ($900).
Based on Bryan’s advice, I’m going to move forward with a Borg-Warner S300SX-E 8380 turbo with twin scroll .91 A/R to replace the dead cheap knockoff that was on there. My wife has kindly offered to make it an early Christmas/Birthday present given all the cost of everything else the car needs. I’m sitting at about $8500 to get this car rolling with everything it needs. I’ll work on the cosmetic stuff over time and the smaller things I can DIY like brakes, interior, suspension, etc.
When I got this, I really wanted to do it all but reality set in and I’m quite sure that spending all this up front will make it less expensive long term and I get to drive it a lot sooner than expected although it will be quite ugly. I’m a little worried about what else we find once it’s running...
08-01-18, 10:49 PM
