First off, a big thank you to everyone in these forums and to the good folks that established this great site. With out you all my Dart would still be running the same as the day I brought it home...like crap.

225 3.7 slantsix
Did a lot of minor work on this engine abount 2500 miles ago. Timing chain, harmonic balancer, carb., fuel pump, never took the head or manifolds off. Got it running perfectly. Other than a alt. relay, no problems that whole time. Did a tune up about 200 miles ago.

Here's whats happening: 125 miles after tune-up valve noise, rattlin and pingin loud. Get home and notice there's a "put-put" out of the tailpipe.
Next day pulled the cover off and sure enough number 3 intake valve is really loose. So I whent ahead and lashed all the valves. Cool, runs great again!

25 miles later same thing. Hmm. Went back in. All rocker arm screws are pretty tight, not new but nice and snug. No.3 intake screw had not moved at all. Push rod is not bent and spins freely. Rocker arms and shaft are fairly clean and oil flows just fine (got that nice kinda weeping-wall-waterfall effect down the push rods) Another valve lash. Notice that I'm running out of threads on the screw. Engine runs great again.

25 miles later same thing. Another valve lash.
This happened one more time and now I am completely out of threads on the adjustment screw. It's about .029 right now and I cannot tighten it any more.

What I did wrong at tune up was that I installed Champion platinum plus spark plugs with a heat index of 15.

I have not done a compression check and I will pull the valve this weekend... well I gonna go ahead replace all the valve seals and clean the rocker arms and shaft while I'm in there.

Dose anyone know right off what's going on with this intake valve? May I have damaged the valve assembly or even the valve itself with too high of a heat index?
Any knowledge on this is greatly appreciated. Thanks!!!

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So...wheres the best place to mount tow hooks?

You say it got looser?

That is probably not the valve. If you had valve recession, the lash would get tighter.

Loosen that one up, and pull the pushrod and then the lifter for that valve. You didn't tell us what year engine this is. If it's a spark plug tube engine, pull the plugs around that lifter, and remove it for inspection. If it's a peanut, you will have to pull the head.

I'm suspecting a problem with the lifter or cam.

CJ

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Part of Tyrde-Browne Racing

My bad...1973...tubes.

Okay, thanks CJ. That makes clear sense to me now.

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So...wheres the best place to mount tow hooks?

Pulled the lifter today and cannot find anything wrong with it. I even pulled another one for comparison. 99.9% sure the lifter is fine.

Not sure what to look for for damage on the cam lobe but what I do see when I shine a light down is two shiny straight lines accross the lobe. Turned the cam via the fan blades to make sure they were not just some kind of glare from the light and noticed a third one.

Are these signs of damage to the cam?

Any input on this is greatly appreciated.

My first engine and I've been so careful on any work I've done. Made sure that I had the right knowledge, tools and time to perform them...and then go off and do a lame-brain thing like put the wrong spark plugs in. Nothing like learnin things the hard way!

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So...wheres the best place to mount tow hooks?

What part of Phx are you in? I may be able to come take a look.

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'72 4 dr Dart
'63 4 dr Dart

Wow, hey that would be great!

I'm downtown area. Thing is I won't be available in the daylight hours until Saturday.

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So...wheres the best place to mount tow hooks?

I work till 1 am during the week myself. Sunday is my only real day off. I'll PM my number and we can work something out.

,Cliff

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'72 4 dr Dart
'63 4 dr Dart

Thanks Cliff!

Give me a little while to call. I'm off to give mom a ride to the airport.

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So...wheres the best place to mount tow hooks?