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Mystery Squeak in Rebuilt Engine

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elysium

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Well at long last we fired up the rebuilt engine today and we have a mystery squeak driving us a bit mad. The noise sounds like you would expect from a dry pushrod -on/off/on/off etc rather than a constant squeal.
Naturally we re-checked everything in the top of the engine. All had been lubed and all was getting lube and turning freely. We isolated and moved each rocker arm to try to isolate the noise but no luck. We double checked the valve guides and the stem seals and everything looked fine. The noise is present even just cranking the engine.
When all of the spark plugs were removed the noise ceased but returned when any one plug was put in so somehow the compression is driving the noise.We are kind of looking towards the crankshaft at present but can't isolate the noise so far.
In rebuilding the engine we had the crankshaft turned and used Helms custom thrust washers and have .006 movement per the manual.Other mods include shaving the head .125 to 9-1c/r,Goodparts GP2 cam with shortend pushrods and single springs,Fidenza flywheel and Patton's TBI system.
I talked to 2 local LBC shops who suggested taking it out on the highway to see if it would wear in or blow-up but I'm kinda hesitant to go that route so far( go figure!)
Any help/suggestions would be greatly appreciated!!!
Thanks,
Elysium
 
We have a new electric fuel pump at the tank and it was delivering 5-6 lbs at the regulator-what would you suggest to look for?
 
Did you check the oil slinger area for the noise? Is the lower gear shimmed properly?
 
Vaccuum leak? What part of the engine is it coming from? Is it metallic or otherwise?
If you have access to a mechanic's stethoscope, go over the engine to try to pinpoint where it's coming from.
 
maybe the crank pulley is loose or not completely seated and is wobbling against the oil seal?
 
As I said on 6-Pack, I may be able to look at the car with you this weekend.

Let me know.
 
Did you chamfer the inner radius of the Helm bearings to match the radius on the journal to throw area of the crankshaft?

See the last three pictures before the Fidanza flywheel.

Thrust Washers
 
Don't think it is anything to do with a belt or pulley. All that has been replaced and we took it all apart today to eliminate it from contention. Also as I said earlier,the combustion aspect seems to point to the lower end of the engine. Paul,I will pass along your comments to Bob in the morning and look into those to see if it will narrow it down at all. We did talk to Eric this afternoon and it seemed to stump him as well,albeit w/o benefit of hearing it.As to the vacuum,the TBI has you use the middle tube and cap off everything else. Only other issue is if something in the TBI itself would be acting up but we will not know til we hook up the laptop tomorrow.
 
Sounds like your car is kin to my car, what with that mystery noise and all. Still waiting to get my video camera back to capture the noise for the world to hear. A squeak.....shucks, that's nothing. Try a loud knock! THAT is unnerving.
 
Water pump?
Mine squeeked initially after my engine rebuild but eventually the glycol coolant lubricated it enough to quiten it down again.
Doesn't explain the noise going away when you pull the plugs though!
 
Putting the plugs in increases compression and downward force on the crankshaft. Older dried out (new) seals can squeak and maybe the load is enough to aggravate the situation
 
Well we spent another day fiddling with the car with mixed results. We don't believe the sqeak is a significant problem as we pretty much eliminated every big problem it could be. We again took out each set of pushrods and idled each rocker in sequence and the noise persisted so we eliminated the valvetrain.
In pulling the plugs we found that a single plug in 3,4 or 5 caused the noise but did not in 1,2 or 6. We scoped all cylinders and saw no problems with piston or rings or signs of damage so we suspect as tight ring or some such minor anomaly.We then spent 4+++ hours fooling around trying to get the darn thing to run for more that a few seconds. We finally ( kind of ) determined that the electric fuel pump won't work unless there is a pretty good volume of fuel in the tank( had drained it for fear of ethonal seperation while laid up and put in @ 3 gals to test but not enough apparently as the new bung intruded up into the tank 3/4 -1 inch to avoid picking up sludge.)
Once we got around that bugaboo we determined that the injectors are being shut down after about 15 sec run time. We have pretty much isolated it to the ECM and will try to further isolate it tomorrow.Quite a process when EVERYTHING is essentially new and you don't know what part or system to trust.
 
Elysium, I've had the TBI setup for a while, so this may have changed, but you said you had 5 to 6 psi at the regulator. Mine has high pressure to the regulator with about 14 psi to the injectors. This could be what's causing the ECM to shut everything down.
 
I had misspoke on that. We originally had wildly erratic pressure but apparantly that was the low fuel-it might have been sucking some air in as well. We have stabilized the pressure at @ 15 lb and now are dealing with the injectors shutting down.With probes hooked to the injector leads we can see the power cutting out prior to the car shuuting down and so far have ruled out power loss or ground faults to the system.
 
and some of us complain about carbs.....
 
Is the 'check engine' light staying on? Even without a laptop, you can put a couple of wires together, and the check engine light will blink to indicate what code has been set by the ecm.
 
We spent another day battling the system and are fairly certain we have a bad chip.The system continued to run VERY rich for a 10-20 second period then shut down the injectors. We were able to swap out the ECM and after a run or two the system was doing the same thing. After much more playing we swapped out the sensor adjacent to the distributor and seemed to have it licked. Still ran rich as all get out but at least it ran. After about 10 starts it was right back to same bit-rich then shut off the injectors.All the sensors were recording correctly and operating with in specs so we have kind of thrown in the towel for now and are trying to get ahold of Patton's ecm supplier in Mi. May find out we fouled something up in the install but we kind of believe the chip is mis-programmed or the wrong one for the car.Only saving grace is that my buddy/mech really pushed for the TBI or I think he would have killed me about now!We've now got the better part of 2 days wasted in trying to get this thing running.No doubt it will get resolved but it does suck right now-I almost have a really nice rebuilt TR6 to play with.
 
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