Exhaust: Hawk sounds sick :(

[kpayne9449]

So I took my Hawk in to a local shop to stop the blue smoke form coming out. The shop told me the seals that were put on were not "grooved" like they were supposed to be. They put new seals on and that seems to have alleviated the issue on the smoke. Now when I start the car though it runs like its gasping for air where it wasnt before. It is difficult to start where it wasnt before the "surgery" and I can feel a little bit of "miss" in the car when I drive it. A slight tug and jerk feeling i guess is the best way to explain it. When it idles it idles rough when i am stopped in drive. As the car warms up it gets a little better but not much. I would really like to figure this out. The shop did say the heads were slightly pitted if that has anything to do with anything. I guess I just don't understand how it was running so smoothly before and now its all over the place. Help!!

[52hawk]

Better get somebody that knows what they're doing adjust the valves before you drive it any more. You didn't mention any back-fire problem,so I assume the plug wires are on in the correct order.

[RadioRoy]

Specifically what seals were replaced? Were they valve seals? If so, something is fishy in the valve train, but before we mis-diagnose the problem, could we have more specifics please?

[r1lark]

Agree with 52hawk, check the valve adjustment. Did they retorque the heads after it was run awhile?

[kpayne9449]

The following is printed on the invoice of things they did:
(before work)
compression 150 psi all cylinders-leak down
test 7-15% on all cylinders, 1 #1 plug head had no gap, regapped all plugs at .32
check pcv system operation-ok
pulled valve covers cleaned oil drains
valve stem seals are up too high , possibly wrong seals

(work preformed)
pulled cylinder heads, added new valve stem seals
cleaned head, checked for warpage, reinstalled heads with new valve cover gaskets
Check ?out? 160 and new head gaskets
serviced coolant, bled cooling system road tested
set ignition timing

That was on the 29th. when I got it home and it was running crappy i took it back.
They adjusted the choke, checked the valve adjustment, checked the timing and filed the points.
They mentioned that I might need a new distributor. I am going today to get new spark plugs as they didnt replace any of these and one was burnt up (they left it in there) The wires are in the correct order and if the new plugs dont work should I work my way back to new wires and distributor cap? there is a little misfire i can hear in the exhaust. It just sounds off. I dont believe i will be going back to that shop obviously. $1400 later. Ugh.

[1954khardtop]

Find someone else to check the valve lash. If they did it wrong the first time they wouldn't find anything wrong on the recheck. They may have adjusted them like hydralic lifters . If so they are way too tight. You should hear a little "clicking" from the lifters at idle.

[52hawk]

That kind of money should have included head resurfacing. And yes,the heads need to be re-torqued after it's been warmed up. The job should also have included new spark plugs,but that's minor. Just the way you described it,sounds like the valves are too tight[as 54 hardtop says] If the valves are too tight,they will self destruct in a short time.

[RadioRoy]

Just the fact that they pulled the heads to install new valve seals, and didn't even grind the valves tells me that they are not worthy of a return visit.

[kpayne9449]

I agree on the return visit. I put new spark plugs in and its night and day difference in the sound of the engine and the feel ofthe gas pedal. The only problem is thesound of the exhaust now, especially in drive. Its very up and down. I took it to a local and he said maybe when the shop took the carbeurator off some crud may have gotten into it. He said i should take the carb out and clean it throughout. I've never done this sort of thing so we shall see. Could it still be the timing is off since the engine itself sounds so smooth?

[RadioRoy]

It's better to do some actual troubleshooting to determine the real problem, rather than continuing to take things apart and possibly/probably cause even more problems. If you take something apart that does not have anything wrong with it, you will often/usually introduce another problem which compounds the original problem. Then you have two problems to fix, each symptoms masking the other.


I would suspect vacuum leaks, since the other shop took off the intake manifold. You can check for vacuum leaks with a spray can of B-12 chemtool, or any brand carburetor cleaner while the engine is idling. While the car is warmed up and idling as slowly as it will, you can spray around the edges of the intake manifold, the carburetor, and the vacuum advance. Any place there is a vacuum leak, the motor speed will change.

Check the dwell, the timing (and mechanical and vacuum advance) and check for vacuum leaks.

The timing light will tell you if the timing is correct and also if the timing is stable, that is, not jumping around. Sucking on a rubber tube from the vacuum advance to your mouth will tell you if the vacuum advance works. Increasing the speed of the engine will tell you if the mechanical advance works.


All these checks can be done with simple tools without taking anything more apart.