Rotary Car Club

Rotary Car Club (https://rotarycarclub.com/index.php)
-   RX-7 2nd Gen Specific (1986-92) (https://rotarycarclub.com/forumdisplay.php?f=37)
-   -   Let's talk about fouled plugs (https://rotarycarclub.com/showthread.php?t=15606)

RICE RACING 03-30-2012 11:33 PM

That is why I am a Don Mega **** Bag :biggrinjester:

What seals did you use?
How was the rotor housing on the front?

As some sort of practical help, if you take it easy and they are factory apex seals it will take about 7000km of daily running to make them flat or conform to housing distortions.

I'd be interested in your compression test to see if this is the problem or not. ;)

FWIW I have "rebuilt engines for a total of $300 for mates many years back, one was a 3am job in his garage replacing a rotor housing with one I use to jack up my car! (filed the rough spots off where the chrome was chipped!) and slapped it back together with new Mazda Apex seals, that motor survived for years at 22psi boost on a T04 and about 480bhp lol, it was how I learned about the power of stock ports. Even on a dodgy rotor housing (by my standards 10 years ago) it still had good compression to not foul a plug, but ran OEm stock 2mm seals.

My world is not much different to anyone else's here, that is why I post up advice (and a bit of a rant some times haha)

JustJeff 03-31-2012 07:21 PM

I used Atkins apex seals, new side seals, new plugs for corner seals, FD springs, all new springs all around. I reused the oil control rings with new springs. I replaced damaged front housing and rotor with used housing and rotor. I checked tolerances with everything that went back into the engine and everything was within spec. It's a JDM engine and was very clean inside. The replacement housing was also JDM and the rotor is out of an FD.

I did a compression test the traditional compression tester way. Engine warmed up, EGI fuse out, CAS unplugged. I took the front leading plug out to test and the rear trailing plug out. I had trouble getting my compression tester hose in the trailing front because of a/c and p/s. I was able to get it in the leading hole and went with that.

Front has even bumps of just over 90 and when I let the compression build it was just over 100.

Rear has even bumps of just about 100 and built up to 120.

From what I've read you want front and rear no greater than 20psi so I'm borderline.

I ohm tested my plug wires
T1=5.47 and is less than 3ft long
L1=8.07 and is just over 4ft long

T2=5.11 and less than 3ft long
L2=8.28 and just over 4ft long

I haven't tested the coils yet, Final Four is on for one, but I also need to read up on how to test the coils.

RICE RACING 03-31-2012 10:12 PM

That sound acceptable to me using that type of tester assuming it winds over near 250rpm test std. Anything reading around 90psi on a normal gauge should not cause plug fouling.

Have a look if you have a leaky secondary fuel injector on the front rotor, you can check this by taking off the top half manifold and simply priming the fuel pump. This is/can be a common cause too.

JustJeff 04-01-2012 12:39 AM

Leaky injector was exactly what I was thinking. I'm occasionally smelling fuel but have no leaks. When I did the compression test on the front rotor I got an initial poof of gas smell and then it was gone.

I had been worried I had a coolant seal leak that could have been fouling the plugs, but I'm not loosing any coolant and I keep passing the bubble test...that and my plugs were dry when I pulled them today.

JL1RX7 04-01-2012 06:28 AM

Jeff I got two 460 injectors off another member and if you want them to use while you send the other ones off let me know.

JustJeff 04-01-2012 08:05 AM

I appreciate the offer, but I'll simply let the car sit and drive the van. I've got 550/800. I've got a RB exhaust, custom TID and Rtek 1.7 on the car. I even though the engine is in break in and not seeing any boost or RPMs above 4k...I'd hate to run the risk of running lean and detonating.

I have a question related to leaky injectors. I had engine parts powder coated and was not thinking about the dampener/regulator in the S5 secondary fuel rail. Should I be replacing my secondary rail because that dampener/regulator could have been damaged during baking?

FerociousP 04-01-2012 11:43 PM

Quote:

Originally Posted by JustJeff (Post 187861)
I appreciate the offer, but I'll simply let the car sit and drive the van. I've got 550/800. I've got a RB exhaust, custom TID and Rtek 1.7 on the car. I even though the engine is in break in and not seeing any boost or RPMs above 4k...I'd hate to run the risk of running lean and detonating.

I have a question related to leaky injectors. I had engine parts powder coated and was not thinking about the dampener/regulator in the S5 secondary fuel rail. Should I be replacing my secondary rail because that dampener/regulator could have been damaged during baking?

The dampner is in the primary rail, the regulator is in the secondary rail. I'd tee is a fuel gauge before replacing the regulator. test are pretty straight forward... but, both the front and rear would be flooding if your pressure was too high.

JustJeff 04-03-2012 05:35 PM

Quote:

Originally Posted by FerociousP (Post 187926)
The dampner is in the primary rail, the regulator is in the secondary rail. I'd tee is a fuel gauge before replacing the regulator. test are pretty straight forward... but, both the front and rear would be flooding if your pressure was too high.

That's what I was thinking. The fuel rail is open so both would flood.

Pete_89T2 04-03-2012 06:01 PM

If you have flooding in only one rotor, it could be that one or both of the injectors on the flooding rotor are leaking down. In other words, the injector is gummed up and not closing fully when you shut the car down, so only that rotor floods.

JustJeff 07-16-2012 09:39 PM

I've been driving the car daily. Fuel injectors were sent to witchunter for cleaning. I still have fouling plugs. So far it has only been the front rotor that is fouling....and I bet when I pull the plugs I'll find the same thing.

WankelsRevenge 07-17-2012 12:41 AM

I havent read this whole thing, but are you still running your OMP? If so could it be an issue with them spraying too much oil into the chamber? Also maybe youre not getting enough spark in that chamber which could be causing you to not get a complete fuel burn. Granted, Im just pulling these ideas out of my head, so Im not sure how plausible they may be.


All times are GMT -5. The time now is 02:49 AM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Hosted by www.GotPlacement.com