I tried doing a search but I wasn't able to find exactly what this is when someone states that the car has a hot start problem. Supposedly easy fix?

 

It depends. In most cases it can be from low compression. Others, like myself get hot start problems from heat soak.

 

Yikes, low compression? not good, going to need to get a test done if i end up wanting to buy it

 

It is usually contributed to low compression or a leaky injector. Definitely perform a comp test before the purchase.

 

Went to go see that car today with the hot start problem. I went to go take the car out to test drive and BAM, I stalled the car because I wasn't used to the upgraded clutch. We had to sit for 20-25 minutes until the car was finally able to start back up with a jump. Car ran great after that though but other than that, I am calling the builder tomorrow.

He built the car from scratch and see what the fix could be, or if he even warranty his work. When I had my RX7, he did work on my car and is well known so I'm confident in his ability. The owner was saying something about it may be some type of spring within the motor or something? I don't know.

 

Missing a spring in the motor? HAHA! I'd stratch that car off your list if so. THATS BAD.

Like mentioned, just compression test it.

 

No it's not missing a spring in the motor lol. The whole car was built by a well known rotary mechanic in the industry as he started building/dealing with rotaries in 1983.

The owner was talking about there is supposedly a simple fix for it, but like I said, the engine only has 2k on it and I will be calling the builder tomorrow to ask him questions about it and will likely get the compression test done.

 

Just got off the phone with Rick right now and I have some bad news.

First and foremost, I asked if he warranties his work on the car and he said that there is no warranty on the engine/tranny because it is considered a "race" engine with the mild streetport done.

The second thing I talked to him about was the hot start problem that we had and he said he would have to see the car and inspect it prior to saying what the problem is. It would be around $90 to get a compression test and for him to take a look at the car.

Once I told him that the car was tuned by Steve Kan, he told me that it could have been a bad tune/timing/etc which creates enough heat to pull the 3mm seals away from the rotor housing creating a slight air gap. When you try to start the car when it's hot the rotors are only turning at about 200rpms and those air gaps prevents it from starting until the engine is cooled.

He said that the car would have to get those seals replaced which he said was a $3,500 job or basically another rebuild.

 

So they build engines they dont warranty? Ill leave that alone as I dont warranty the engine once it changes hands except a few rare instances. However, who builds a motor with a mild port and doesnt warranty it?

Sounds like atleast they were honest about the engine and wasnt lieing to help their customer sell the car, you would be surprised how often stuff like that happens. Either way, use the info you gained as a bargaining tool and have the engine rebuilt somewhere else. If they used new housings on the last build the housings, bearings, most springs, etc should all give you a good platform to rebuild from for a decent price.

 

Yea, Rick is a top notch guy and like I said, he's been dealing/building rotaries since 83. I talked to the seller and told him about the problem. Seeing that it'll cost $3,500 to replace the seals, what do you guys suggest for the offer? On craigslist, he's asking for $17,500 but he has had it on the forums for 15obo. When I talked to him yesterday, he said he would take $16,000. Since his other one said, 15obo, I'm thinking of taking 3,500 off of that and doing 11,500 but I doubt he'll take that since he's put around 30k into the car. Only 64k on the chassis and 2k on motor/tranny. Here was the mods list

1994 Touring Edition (moon roof, leather seats, boss sound system, etc.)
5spd Manual
about 68,000 ORIGINAL mi
about 2,000 mi on newly rebuilt ENGINE
about 2,000 mi on newly rebuilt TRANSMISSION

Engine Rebuild + Mild Port (this included NEW rotar housings, 3mm seals, etc.)
Unorthodox Pulley Set
APEXi Power FC + Commander
HKS Twin Power Ignition System
Newly Rebuilt w/ same miles on it as newly rebuilt engine.
Stage 3 Clutch and flywheel
A-Spec 500R T4 Single Turbo
A-Spec Stainless Manifold
Boost Controller (is also used as the boost gauge and fits in the a-pillar gauge pod)
Greddy Type-RS BOV
Tial 44mm Wastegate
RE-A Dual-Tip Cat-Back Exhaust System (JDM)
A-Spec Down Pipe
A-Spec Mid Pipe
RX-7Store V-Mount Intercooler Kit + Modified KOYO Radiator
Greddy Throttlebody Elbow
FDNewbie Import, Dual Oil Coolers w/ Black Setrab Cores
Coolmist Never installed WATER INJECTION KIT I will include w/ the purchase of the car
Eibach Pro-Kit Springs
Tokico Illumina 5-way adjustable gas Shocks
Received a completely NEW Montego Blue (same as stock color) Paint job.
R1 front spoiler
Greddy Strut Bar
Short shifter
New Miata Battery has been relocated to bin behind passenger seat (very popular location)
A/C Delete

 

Sounds like a $10-11k car to me, you will have around $15k in it when finished so compare that to what is on the market.

 

I will have around 15k into the car when finished? What do you mean by that? It'll be around $5,000 to get the car running in perfect condition?

 

The rebuild itself is $3500.00 not including install and it has fresh everything? Good lord I need to move to Cali All that needs replaced in the engine is apex seal springs, apex seals, coolant seals and o-rings, and oil control rings. Roughly $500.00 worth of stuff.

So take into consideration the time and money you will have in this car, is it worth it to you? That is what matters. However, for around $17k you can have one hell of a fd with some nice expensive aftermarket wheels and the mods you mentioned.

That is just the opinion of someone who has owned a lot of these cars, however, it is your money so do as you wish. It still isnt a bad deal at around $17k but you are going to have another $600-1000.00 in getting another tune as something is obviously wrong with the current setup.

 

I think $3500 is the price of having the car fixed which is basically a rebuild, that is including pulling/putting the motor back in.

Like I said, his craigslist ad is 17,500, but I found his ad on here in which he is asking 15,000OBO. Since it's supposedly a $3,500 fix and the builder even told him that the engine will need to be rebuilt in order to fix the hot start problem, I would offer $11,000 and see where we go for there. I am in no rush to buy since the RX7 will be a weekend car. So if I get this car for $11,000 I can have it in the shop getting everything correct.

It has a Steve Kan tune right now, and Rick says that the timing or fuel or something within the tune may be what's causing the car to act the way it is. Is there a way to load a safe basic map to see if it fixes the problem?

 

Yeah, you can do that through the PFC Commander, look in the settings.

 

I warped 2 sets of mazda 3mm seals, found the cause to be lack of lube. The omp running 2 stroke oil wasn't enough, had to premix as well. Once I started premixing it stopped warping seals. Something you might try that worked for me was to drive the car withount any omp or premix for 500 miles. Doing that wore my seals back to flat, and I now have 115psi comp with a large street port. This was suggested to me by 2 respected engine builders.

 

I have also seem many cases where seals warped due to careless/aggressive tuning. A 3mm seal is more likely to warp than break. Also, ALL 3mm seal motors really need to run premix. The stock omp system really doesn't provide enough oil to sufficiently lubricate a larger seal. Any competent tuner should know this and verify that premix is being used before pushing the car. You can try to run the car as suggested and see if the seals wear in, but you will also be putting excess wear on the rotor housings. I guess you need to decide if the car is worth the asking price and assuming it will need a rebuild. You really don't know what internal parts it will need until the motor is apart.

 

That's what Rick was saying. That the 3MM seals may have warped, but he also said that if they were the problem of this hot start, that they would correct themselves over time. The motor now has 2,000 miles on it. If it were not the seals, wouldn't this problem be fixed by now? Also, if I were to set the map to stock on the PowerFC, is there any chance of damaging the car even more or will the PFC stock map be safe for the cars setup?

Also, what is this premix you guys are talking about? If I do end up buying the car, I may have to try and see if this works.

Either way, worse case scenario is the motor will have to be rebuilt and torn apart. I made a 11k offer (4k off his asking price) and he said he can do $12k. Since I'm in no hurry to buy and again, I don't know exactly what the problem is (what if I do rebuild the engine and the problem still exists!) I am going to stay firm on 11k.

 

The stock PowerFC map is very rich for the stock twins, I think. I would just say run the stock map and don't boost. Also, get a retune asap.

Also premixing is the act of putting 2 cycle engine oil into your gas tank. It's supposed to help lubricate the seals much better.

If you rebuild the engine and the problem still exists then it means that it's something else. I think the car is worth 12k with those upgrades, but I'd want to see pictures of it's condition.

 

So if I do end up picking up the car, what should be the first things for troubleshooting the problem, being the replacing the seals as the last resort.

If I get it, I should do the premixing first? Where can I pickup 2 cycle engine oil and how much do I put into the tank? How long should I wait to "test" if the starting problem has gone away?

Second would be to get a retune correct? The car runs and boosts great on the map that Steve Kan tuned it on, but if his tune is the reason for the car not starting after it is warm, then I would be glad in getting a new/better tune.

 

Wow, this theory sounds interesting. I've never heard this before. What was your compression before?

 

really?? explain your many cases where aggressive tuning warp seals.

 

Was down to 70,even getting hard to start cold. Since then the car was tuned(by Kan) to 430 hp on a superflow. I know have about 5k on the motor and it runs great, I have 15 inches of vac at 1000 rpm on a very large street port.

 

I would honestly try to put about 500-1000 miles on the car right away staying out of boost and see if the seals correct themselves. There are cases where the seals will become "unwarped" and wear correctly to the housing, I wouldnt be betting on it but it is worth a try, however, I would not recommend running no premix or omp as it will eat at your housings in a hurry. If you do decide to run no omp or premix I would just let the car idle for 6-8 hours and wear in that way, I would not suggest driving without some some of apex seal lubrication, especially if the engine has new housings.

 

Aggressive timing, or overly lean conditions will skyrocket egts, thus warping seals. Careless porting of the exhaust will also do it. I have seen it many times and had to fix a motor like this a couple months ago. The motor ran but was low on power. Upon taking it apart the seals were found to be warped. If you took two seals and held them against each other you could see a significant gap. A couple well know racers had this problem as well and found certain seals can't take as high egts and have to be run richer. Until that motor is apart you won't really know.