Whats up everyone? Today is the third day that I've had my FB running, and i've had a couple of issues (both, i'd say, are rather serious) crop up on me.

First of all, I have an oil leak that just started. I got her up and running, and went to check my fuel pressure. It was up to 7psi, but when I was checking it, I felt a drop of liquid hit me in the chest. I looked down, and it was brown! I looked at the only external moving part of the engine (the accessory belt), and it was slinging oil everywhere! I promptly killed the motor and went about cleaning up the mess. The oil was a dark, dark brown with a sludge-like consistancy. Once I got everything cleaned up, I re-fired my motor and went about searching for the cause of the leak. I couldn't find anything. The three parts that were covered in oil the most before I cleaned were: OMP, dizzy/dizzy port (or whatever you call the orface that the dizzy goes into), and the passenger's framerail. I had splatter on the drivers frame rail, and on the top of my RB triangulated strut brace and on top of my RB carb hat. I'm thinking that it's either a tension bolt leak, a OMP leak, or a leak around the hole where the dizzy goes into the block. Is there any easy way to figure it out?

Second I consider a bit more serious. After I cleaned up the oil, I revved it a few times to put alot of oil pressure in the system to see if I could see anything leaking. I couldn't, but after I let it return to idle, it sounded rough and the motor was shaking a little bit. **** i thought. I went around to my drivers seat, and my eye was caught by my mechanical oil pressure gauge. It had been reading a little bit over 20psi when I first fired her up, but now it was sitting at just under 10! Needless to say, I shut her down immiediately, and started to look for more oil leaks that could be causing the pressure drop (hot, thin oil will find its way out of the motor more easily than cool, thick oil). Once again, no oil leaks. I think that it's because I need an oil change (I only have ~700 miles on this change of RP 10w30, but it's been a year since my last change). Could this be old oil, or do I have a more serious problem? I'm going to pick up 6 quarts of RP and a new filter this weekend and change my oil, and i'm going to cut open my old filter to look for copper shavings. I'm going to be PISSED if i've eaten my bearings.

Thanks for your help.

 

to the top for the start of the workday

 

the first problem is that you're running 10W30. you need to be running 20W50. have someone rev the engine so you can visually look for leaks. its odd that the splatter is so inconsistant. however, the fan may have something to do with that. you can always remove the omp and clean it and reinstall it with a new gasket and go from there. check your omp lines for any breaks or leaks at the carb. perhaps a pic here or there would help as well.

 

i'll snag some pictures tonight. I was told that you don't need to run 20w50 on a rebuilt motor because of tighter tolerances in the bearings, and 10w30 is perfectly alright. I'll check for breaks in the OMP lines, but the actual OMP looks extremely new (all shiny and not gunked up), and the rebuild has 6-7k on it, so i'm pretty sure it's not a leaking OMP.

 

i wasnt aware that it was a rebuild. i would double check on the oil weight issue. all rx-7's came with 20W50 from the factory. i'm sur some people use 10W30 in colder conditions but most people here will reccomend 20W50. if its a fresh engine you might be able to see where the leak is quite a bit better. i'm thikning perhaps that the seal around the eccentric shaft may have failed... have you inspected that area?

 

The PO told me that it had 5k on it when I bought it, and I've put at most 2k on it since I bought it. It's a little bit hard to see where the leak is coming from because of all the **** that's at the front of the engine. It looks like i'll be spending a bunch of time really cleaning the front of the engine bay tonight so I can find where this damn leak is coming from.

the strange thing with the oil is that it's a milk chocolate color, and the consistancy of melted chocolate, almost like a sludge. It's not like any 10w30 leak i've ever seen. The accessory belt is the culprit of spraying the oil all over the engine bay, because it's as clean of a line as you'll ever see as far as oil spray, inside the engine bay (on the passenger's frame rail, on the dizzy port, and on the underside of the RB Brace). I'm going to be pissed if it's a main seal. I have a 68k block sitting at my Grandpa's house, but I really dont' have the time to swap motors (I dont' have the tools at my parents house, and he lives an hour away).


How about the Oil Pressure issue, does anyone have any suggestions on what that could be?

 

You have coolant in your oil, you f....up. Do a compression test, post the results, and find someone who can pressurize the cooling system and perform a leak down test. Change the oil immediately, if it turns to a milkshake color again, you will need to tear the engine down and find the coolant leak that's getting into the oil.

My guess is the the waterpump has lost it's seal and it leaking from the weep hole at the underside of the wp, right behind the pulley hub. Check your coolant for oil contamination too.

mazdaverx712B, the engines came with 10W30 from the factory, that's the appropriate oil for breaking in a new engine. If you look though the owner's manual or the FSM, there's a chart showing which oil weight for which temperature ranges. 10W40 and 10W50 have the broadest range of any of the multi-weight oils. 20W40 is a good choice for temps that aren't below 20F. Some engine builders feel that the 20W50 is to broad of a range of weights.

 

Thanks for being brutally honost and to the point. I already have a compression test on the docket for this summer, once she's ran for a while and gotten the seals back used to running (9 months of sitting every year doesn't give very good compression after only 3 days of running). The oil in the engine is a brown/purple color, like slightly used Royal Purple. The actualy engine oil isn't a chocolate color, just the oil that's being slung in the engine bay. I'll post pictures of the oil on my dizzy (didn't clean that off so I could get a picture of it in better light). Today is payday at my other job, so I'll pick up 6 quarts of RP and a filter and do a change, and post pictures of the oil that I drain and what, if anything, i find in my Oil Filter.

Also, if I can't find my wrench for my Aeroquip lines, what is the best way to not damage the fittings on my oil cooler (I want to drain that SOB as well)? Am I going to have to pull my oil cooler completely to drain the oil out of it, or is there a drain plug on it (i've never looked at my FMOC)?

 

i did look and you are correct, the owners manual shows 10W30 in a broad range. i can understand using it for breaking in an engine but not for every day use. i just wouldnt feel comforatble using it after using 20W50 for this long. thats just my opinion on that in conjunction with what the owner's manual states on viscosity.

 

Yeah, I've been accused of giving some blunt reality checks, but there's no point in dancing around the issue or sugar coating it. If the oil is foamy at all, then there is water mixed in with it. It's called emulsification when they are mixed. i drained 15 qts, of milkshake foam out of the 283 in my 57 Chevy when the block cracked.

The plug at the bottom of the fmoc isn't a drain, it's the thermostat, but you can use it as a drain. That's safer than breaking open the oil lines and it will drain more oil out through that plug. If there is the possibility that coolant has mixed with the oil, save your money and use dino oil for this oil change. If it stays clean/non-foamy, then you can change back to the RP synthetic once you've tracked down the leaks.

Have you been losing any coolant? What's the pressure rating of your radiator cap. The FSM calls for 11-15 psi, most use a 13 psi cap. If you need to drain/flush the coolant, there is a drain plug in th block by the driver's side motor mount

 

I'll change the oil with some regular 10w30 dino juice. Murray's is running a special, Mobil Clean 5k for 1.29/quart.

I havn't been loosing any coolant. I have a bad sensor that turns on and off my "low coolant" light, so I keep an eye on the overflow bottle all the time, and it's full with nice, green coolant/distilled H2O right now. I'll pull the rad. cap and check the color of the coolant in there tonight. I am pretty sure i'm running a 13psi cap right now.

Thanks for the info on the thermostat on the bottom of the FMOC. Should I be concerned with any sort of corrosion and breaking that?

and BTW, it's nice having someone else that gives reality checks to people. I got bitched at by my mom about being too mean of a person.

 

Checking the overflow is fine, but it's not always an indication of the coolant level in the radiator. Corrosion shouldn't be a problem breaking the plug loose, but PB Blast it just in case. I use a big ***, heavy crescent wrench. Make sure the jaws are adjusted tight, then give the handle a sharp rap with a hammer to break the plug loose. Trying wrench/pull on the handle often rounds the plug and stresses the fmoc mounts.

 

i've checked the coolant level in the rad. in the past and it's never gone down. I'll hit it with some PB tonight when I get home from work, then go and pick up some oil and a filter, and then go about changing the oil, and possibly the coolant.

would you suggest the same thing with the coolant plug if i need to drain the coolant, putting on a crecent wrench and smacking it?

 

So I changed my oil tonight and cut open my oil filter. There was absolutely no water in the oil, it was just a little bit dirty, but not murky, and there was no water on the top. I couldn't get the thermostat off of the bottom of the oil cooler, so I just removed one of the lines and drained it out from there. I broke the mount on my rad. that holds the passenger side of the oil cooler, so I'm going to have to fab up something to fix that. I cut open my K&N oil filter and didn't find any bronze shavings. I fired up my motor, and was seeing ~40psi at idle. I revved her a couple of times, and heard a belt squeal, and then it idled kind of funny, and my oil pressure dropped to 20 and kept on falling, so I killed the motor. Checked under the car and there was about a 3" circle of oil under the cross member, and it was dripping. I climbed under (it was sitting on jack stands), and there was oil all over under my Water Pump. It was murky, and a bit green, so I knew that's where my oil leak was, and what was causing my pressure drop. Needless to say, i'm going to pull the water pump off of my spare motor and toss that on with a new gasket, and see if that helps me out at all. I was a little bit low on coolant, but not by much, so I topped it off with a 50/50 mix and called it good. I am going to let it cool overnight and then check out the color of my coolant tomorrow.