OK, I finally got some decent weather on a weekend and tore my plugs out. I ran a compression check and found:

1-125
2-120
3-100 (112 with oil)
4-125
5-120
6-125
7-124
8-75 (85 with oil)

I'm guessing #3 and 8 need rings and that #8 has a burned/non-sealing valve.

All plugs were ash grey on the tips, #8 less than the others.

Advance is 11 BDC and the truck runs ok with slight hesitation on acceleration once in awhile but I have been chasing down vacuum leaks.

My plan was to install a 4 bbl manifold and carb with a rebuild in the future. Do you think I should get a valve job done too? I didn't want to go that deep yet but....

The truck is used mostly for daily around town driving, I just want a little better fuel economy and a little more punch at the stop lights.

Also, how much should I expect to pay for a valve job in both heads, give or take (probably just a re-grind I hope)?

 

I would get a valve job done, and atleast get a rering kit.

 

Take the heads down to your favorite machine shop and have them inspected. If they need a refresher, could be about $200 (i don't have my handy cost sheet handy though). Since you have it apart, you can pick up a cast 4 brl and used carb for about $100, toss it on there too.

--Mike

 

when i had my heads redone it cost approx $350 for the following:

new hardened seets
milled .10
hot tanked
new stanless valves
checked for cracks

 

You're gonna need at least one exhaust valve, #8 is burnt. Try to separate the #7 & 8 plug wires so they're not together. I would recommend a new timing chain too. A worn out chain will jump after a valve job.

 

I promised the guy the money for the carb and intake already so I wiil go ahead and get that ($125 for cast iron and fresh Autolite). I will then get the heads redone. Be just about normal to get the heads off and see a scratch in a cylinder wall. LOL.

Thanks for the figures on cost, I don't want to get ripped off. Funny how these trucks will run forever when you don't do anything but change oil and add gas. Just seems to cause probelms when you look too hard. I have seen an "other brand" engine from the fifties running in its third body with out bearings. Owner brought it in saying it knocked a little.

I think I will try and leave the block alone as I am trying to get money together to rebuild it to a 390. Gotta pinch a few pennys for that one 'cause I want to do it fairly right.

Thanks all.

 

Off base slightly-- hope you don't mind! fordman where did you get the stainless valves?

 

Not real off base, I guess I should probably do the right thing now so when I get the 390 together the heads will already be done. I would like to run a mild cam later so I need info on stock style (quality) rockers, springs, valves, etc. I don't want to set up rollers.

Just so I am not double tapping targets, I have been trying to compile information off archives on what I want build into my engine. This will go into the mix. Thanks.

 

Putt:
If you need SS valves, I have someone you can call.

76r:
Your guys at the machine shop, if good, will set you up depending on your needs and budget. Discuss with them the bottom line basic rebuild and then go up from there. You can get all the way into well massaged heads with CJ size valves (but they will probably not work on your stock bore block).

--Mike

 

Mike, you can probably post the name and contact info of the company if you like. No rules against it! If you don't want to for some reason then that is cool too.

 

That's cool, I already let Putt know but for those others interested.

Give FTE'r Rob McQ at Blue Oval Performance a call (303-762-8298).

Unfortunately for me he is just down the street and I don't have extra $$$

--Mike

 

#3 and #8 definitely have ring sealing problems. Oil doesn't do anything to help a burned valve, so I don't agree that's what's wrong with #8..

I don't agree with those here who said go ahead and do a valve job. My experience has been that pulling the heads off a worn engine and redoing the valves is only going to make the ring sealing worse. When you retorque the heads, you create a new cylinder shape pattern that the rings have to wear in to in order to seal. With 3 and 8 already dodgy, you're probably only going to make things worse.

 

I was going by the fact that the oil trick only bumped compression by 10 psi (that should be rings), #3 doesn't bother me 'cause it's only a few psi from the rest but #8 is quite aways down from the rest.

The engine is only a few months from being rebuilt/replaced anyways. The truck is fine and has probably been like this long before I got it. It doesn't go very far as I live 5 blocks from work and once in awhile a ten mile trip at city speeds to the storage shed, no real heavy loads.

I wanted to put the 4 barrel and rebuilt heads on it more to measure the enhancment it would bring and to spread the cost of rebuild over a couple of months. If I went to the junkyard and bought a used engine I will probably run in to the same readings on differant cylinders. LOL

I can't picture rebuilding an engine that is over 100,000 miles without boring it out a little so a little bit of non-standard wear wouldn't be an issue. I am trying to figure out the cost of gaskets, etc. to see how much I would be wasting with my "test". The only thing that would hurt me is a catastrophic failure and I don't see that happening. FEs are too tough.

After rereading my post I think I need to get a real cool name like you'all got. Ratsmoker, scroob, MikeG. seventysixer just isn't cool enough

 

scroob, the oil trick didn't bump up the compression enough to show a ring problem. #8 only went up 10 pounds from 75 to 85, that's a valve problem.