Valve train rattle

[clazar]

1970 RR 440+6 auto trans. I've had some valve train rattle for a couple of months now & want to try & fix the problem. The noise seems to be coming from the dr side frt of the engine. i've used good racing fuel mixed with 93 octane. So i don't think it's that problem. But sometime when i accelerate i hear this "rattle" in the engine. I've replaced all the lifters & checked the pushrods. What else causes this ???

Chuck

 

[sleepar]

Ignition Timing

 

[clazar]

At idle i have it set at 5 deg advanced. That's what it should be with an auto trans. Should i try higher or is that wrong?

Chuck

 

[benno440]

i thought approx. 10 * advanced was a good starting point for a stock 440. am i wrong?

Could just be you need to adjust a rocker? are they adjustables? if not might have a lazy lifter

 

[clazar]

i'll try 10 deg & see if anything changes. its all new lifters.

Chuck

 

[benno440]

comp cams lifters?

i put 4 brand new sets of comp cams rubbish in and everytime there was at least 4 dropped lifters. changed to lunati and not a problem.

i have heard a few other comp cams stories as well

 

[sleepar]

If it does it all the time it's lifter on hard acceleration timing... 10-12 but there is more to it if the advance is not coming in note the ° @ idle/ 2500/ 3500/ 5000 all in by 3500 but not everyone is going to be the same... coil have a lazy vac pot.... many things....

 

[Funship32]

You wrote "But sometime when i accelerate i hear this "rattle" in the engine." Define 'sometimes' and when is this sometime? Seriously, it is all part of troubleshooting an intermittent problem. For example, does it happen when the engine is cold or only when warm? Does it happen when you are downshifted or not? And what about your acceleration...light accel or heavy, foot mashed to the floor type? My thinking is this: You are running a decent octane so unless your timing is off badly....but if that was the case I would suspect it would rattle all the time when accelerating and not just 'sometimes'. And if you have power steering...it could it rattling or possibly something hitting somewhere.

I know it isn't much help but there is a key to when it does it. Once you figure that out then you can figure out the why.

 

[sleepar]

Sometimes a fan will interfere with the shroud and rattle under hard acceleration

 

[clazar]

First off, there is some valve train noise at idle. Sounds like a lifter, but i changed the entire dr side bank of lifters with decent comp cam lifters. After changing them the "lifter" noise is still there. But under half pedal acceleration i hear some rattle noise from only the dr side bank of the engine. When i changed the lifters i checked for a bent pushrod. I'm not sure what the noise is. i didn't know if a valve job is needed or not. Also the rocker arms are getting oil. So i know it isn't lack of oil.

Chuck

 

[sleepar]

Why not change all the lifters ? Set the timing right then see what happens... how can you tell it's from the drivers side from in the car? You're sitting left of both banks of cylinders..... sometimes a weak coil or plug gap and not enough advance and some crapy fuel... but since you have had lifter problems anything is possible in there.... some brands of lifters are lazy on pumping up and or dirt in the oil can plug them so it allows some valve lash under acceleration does the oil pressure drop on acceleration?

 

[clazar]

About 2 yrs ago i had a collapsed lifter. I then changed all of them at that time. The sound is definetly coming from the dr side of the engione. i had someone with to listen & confirm it. But at start up & idle i do have what sounds like a lazy lifter noise. The noise does continue while driving the car. Then under some acceleration i start to hear what i term as a rattle from the dr side bank of the engine. Also the noise continues briefly under decelleration also.

Chuck

 

[sleepar]

Timing.... 10° -12° @800 rpm.... Or poor fuel. Doesn't sound like mechanical problems...

 

[clazar]

I'll give the timing a try.

Thanks
Chuck

 

[clazar]

i went & checked the timing. It is so far retarded i couldn't believe it. i then tried to adjust it & the car was trying to stall after setting it. it didn't want to run. NOW WHAT ??? Something came to mind. After i got the car i noticed that some engine work had been done on it by probably not a Mopar guy. The distributor was set in wrong. i mean the oil drive gear wasn't put in properly & the distributor was set according to the oil drive gear. I have timed it to 5 deg advanced before, so what could be causing this now.

Chuck

 

[sleepar]

Turn the distributor back and forth slowly while it's running and find its sweet spot the mark on the balancer could have slipped and the light would be useless.... ad Vance it a hair at a time till you find it likes it.... Or it could be a shot distributor..... that won't hold time.... no matter where the slot is in the drive gear it will work may have to move the plug wires over a hole on the cap if it doesn't turn because the advance hits the intake.... keep at it you will get there...
Mark it ever it idled the highest as a starting point. Forget the light if it was way off and won't run any where 10 or 12... because it should.

 

[benno440]

shouldnt be stalling if your advancing it as the revs will be going up.
how could it be retarded? i thought you said it was at 5* advanced?
distributor only goes in 2 ways. get it back to how it should be and then retime it. I am not sure i understand what you mean by the oil drive gear in wrong, it slides into the oil galley hole and the gear matches up with the cam.
I still think you have a lazy comp cams lifter. i know it is costly but get a different brand lifter set and go from there. at least pull the cover and check the gaps on your rockers, it will tell you right away.

 

[clazar]

The ignition was changed to Mopar electronic before i got the car. But i did put a new mopar distributor in it a year ago. Thats when i timed it to 5 deg adv. The car starts perfectly. Do you think the damper slipped? or ??

Chuck

 

[sleepar]

If it's not anywhere neer 5° has to had slipped.... like mentioned above get it back and go by ear without the light find its sweet spot then shoot a light on it. The damper if it is original is only a ballpark at best anymore... check the lifter also... if the timing doesn't cure it.

 

[clazar]

Well i put the timing light on it & the timing mark on the damper is probably 30 deg off. It looks like the damper needs to be rebuilt. About a year ago i put a electronic dist in it & everything was fine then. So it's off to Damper Doctor for a rebuild.

Chuck