Asking for help with noise (clutch) diagnosis

[QB93Z]

Originally Posted by Duff

.......Part of the reason I bought the car was to maintain and service it as a hobby and learn more about the mechanics so I'm kind of looking forward to it.

The information available hear is outstanding.

Good attitude! Plenum Pulling is the rite of passage of ZR-1 ownership. It is not really hard, just intimidating the first time.

Call he if you need a tech assist.

Jim
443-244-1347

[secondchance]

Originally Posted by QB93Z

Good attitude! Plenum Pulling is the rite of passage of ZR-1 ownership. It is not really hard, just intimidating the first time.

Call he if you need a tech assist.

Jim
443-244-1347

We've been under there so many times we can do it blindfolded, right?

Many of us have replaced injectors so if any question, there are plenty of us who can help on the forum.

[gbmidyear66]

I bought the Multec "Look alikes" for $549 - I believe they are built in same SMP factory as the RC's, and are disc type.

I couldn't find a good reason to pay the xtra for teh RC's, and I didn't like the idea of "Rebuilt" in jectors (which as I understand is not even possible)

[Duff]

Originally Posted by gbmidyear66

I bought the Multec "Look alikes" for $549 - I believe they are built in same SMP factory as the RC's, and are disc type.

I couldn't find a good reason to pay the xtra for teh RC's, and I didn't like the idea of "Rebuilt" in jectors (which as I understand is not even possible)

How long have you had them in and how are they working out? I like the idea of look alikes and, as I understand it, they are OK with the fuel additives. Also, they are ready to install. I'm torn between the FIC's and the Accels as recommended by M. Haibek. I know the Accels have a good track record.

[gbmidyear66]

Re Accell Vs the FIC "Multec Look alike". I could find nothing written to differentiate between the performance of these 2 products. I am happy with mine - idle is now very smooth @ hot and cold temps.

I think you are not down to the difference in $ and personal taste. I chose the look alikes to maintain a stock look (probably my latent NCRS tendencies)

[Duff]

Done!

Completed coolant system flush and refill last night and went for a test ride. She ran like a Swiss Watch. Un-friggin believable!

No rattle at all, the idle is smooth, the clutch is smooth, and the vacuum leak is completely gone.

Things I did:

Replaced clutch slave and fully bled system
Removed plenum, fuel rails, coil packs, Vac reservior, and secondary solenoid
Cleaned valley and everything in it - wasn't too bad
Tightened breather and intake housing bolts and breather hose clamps - loose
Tested vac system and installed zip ties on connections
Replaced secondary solenoid - source of vac leak
Replaced injectors with Accel injectors
Tested fuel system for leaks
Tested secondary solenoid and actuators
Replaced MAP tube - rotted at plenum barb
Put everything back together
Flushed cooling system and refilled with new coolant - no air lock

Thing is, it ran pretty good before (until the rattle), but not like it does now. It's like the car is saying AHHHHHHHH Thank You. I just didn't have anything to compare it to, but I do now.

Not that I'm breaking new ground here, but I absolutely enjoyed the whole process and learned a lot at the same time. I almost can't wait to get back in there.

Thanks again to those who offered their help, Mark H., ZFDoc, Jerry's gaskets and the unbelievable support for this car.

[Duff]

Dynomite,

I'm 99% sure it was one or more injectors failing that caused the noise. They tested OK cold but I'm sure they were failing hot. This has been discussed in may threads and documented by Mark H. among others.

And yes, forgot to mention I blew out the drain tube. Thanks for reminding me.

The other guys are the experts, I just consolidated the list. But looking back, if not already completed, I would recommend to everyone that the listed items be done as maintenance rather than out of necessity. No matter what the mileage is, they are mostly age related not wear related.

By the way, I can talk to a resource like Mark H. just by picking up the phone and Jerry at Jerry's gaskets hand writes an apology for not shipping the same day because he took a days vacation. How cool is that?

[secondchance]

I am glad to hear that you got everything sorted out.
I've been there. I know how it feels.

[Belsy]

I know it is behind the successful discovery but my '90 had loose cat guts and it sounded like the clutch or engine had serious problems. Emptied cats and all was great!!

[Paul Workman]

Just got my engine back (gonna set it in the car this morning) after a bad exhaust valve was discovered.

It was the damnedest thing - looks like some metal on about 10mm long and 1-2 mm deep along the valve at the seat contact was, for better explanation, extracted! (The seat, except for some slight roughness your could just barely feel around the circumference, showed little damage to the naked eye.)

It is still unclear what may have cause the problem, since none of the other valves - even the other exhaust valve in that cylinder - were affected.

Conjecture at first was the engine ingested something. However, this was marginalized as there was not a single nick or scratch anywhere on the piston to support a foreign object loose in the cylinder. However, the machinist at AES suggests the valve surface was melted. And, after some cleanup and a closer look, he may be right.

What would the root cause be to affect just one valve on just one cylinder? Foreign object? Defective valve? Bob G (who has forgotten more about engine building than most of us will ever learn) suggests it might have been caused by a bad injector!! (Worth repeating)..."A bad injector"!

My point in all this is that the ramifications of a bad injector (or more) possibly extends to more than a little noise from the DM flywheel/trans, or a "little" power loss at throttle... Just something else to consider before shrugging and thinking, "Yeah, not too bad. I'll get around to changing them - maybe this winter!"

Just a thought.

P.



W