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Mon Nov 11, 2013 3:09 pm

Last week my car started to run poorly on my way home from work about 1 mile. It sounded really loud like an exhaust leak but lacked power as well. There was popping coming form the right side. Today I went through and entire tune up only to have the popping still there. After tinkering with it, I feel I have isolated the problem to cylinder #1. Strange part is that it runs better with the spark plug wire disconnected (no popping but lacks power) . So can I assume that the problem is likely inside the cylinder head? Anything else to check?

Mon Nov 11, 2013 3:12 pm

adjusted the valves first? I don't want to jump to conclusions but sounds like a valve issue

Mon Nov 11, 2013 3:35 pm

I'm wondering if it isn't an ignition issue like a cracked cap causing that cylinder to fire at the wrong time. Electricity follows the path of least resistance, e.g., if there's a crack between 4 and 1 it may be trying to fire #1 on #4. Just a thought.

Run a compression test and that should tell you if it's an internal engine issue or not.

Mon Nov 11, 2013 3:52 pm

Tram wrote: I'm wondering if it isn't an ignition issue like a cracked cap causing that cylinder to fire at the wrong time. Electricity follows the path of least resistance, e.g., if there's a crack between 4 and 1 it may be trying to fire #1 on #4. Just a thought.

Run a compression test and that should tell you if it's an internal engine issue or not.

Erik, I did adjust the valves and #1 needed minor as both intake and exhaust were a bit tight. I will swap caps and see what happens. I have to buy the tools to check the compression so that might not get done today.

Mon Nov 11, 2013 5:46 pm

Checked the caps, same result. I guess on to the compression test

Tue Nov 12, 2013 1:36 am

ibjack wrote: Checked the caps, same result. I guess on to the compression test

leakdown tester will be of more use if you have a compressor.

Thu Nov 28, 2013 10:01 am

So I have come to the conclusion that it is the head that needs fixing. I have a set that I can use. Other than just being lazy, would I be better off just replacing both sides or can I do the one and be good?

Thu Nov 28, 2013 10:16 am

ibjack wrote: So I have come to the conclusion that it is the head that needs fixing. I have a set that I can use. Other than just being lazy, would I be better off just replacing both sides or can I do the one and be good?

I'd think you should be able to do the 1 side. But, IF you do both, then the engine will stay balanced. Are both heads off a type 3 engine? Or a bug engine? Just asking, as the bug engine will have a step in the head, and that'll drop a couple of points of compression, compared to using type 3 heads.
It's your call.

Thu Nov 28, 2013 11:04 am

They are correct t3 with a 311 part number. They are the ones with the round base where the rockers mount

Thu Nov 28, 2013 11:16 am

ibjack wrote: They are correct t3 with a 311 part number. They are the ones with the round base where the rockers mount

If they look like the ones on the car, then you should be good to go.

Thu Nov 28, 2013 2:49 pm

Engine out and heads removed. Here's what I found. Bottom right is the number chamber. Looks and feels like the #1 intake valve is seated too far down, but I'm not too knowledgeable about engine stuff. There was a lot of oil on the 1&2 side compared to the 3&4 side.

Thu Nov 28, 2013 2:50 pm

Here's a picture of the P&C after being cleaned up a little

I'm going to get a seal kit on Saturday and put it all back together and see what happens

Thu Nov 28, 2013 6:11 pm

I have had my head studs start to pull out of the case and the result was lack of power and sounded like an exhaust leak. Just a thought

Thu Nov 28, 2013 8:42 pm

Looks like #1 has been leaking for quite a while. It almost looks like that head has been loose for a while now too. As for the valve seats, I really didn't see anything that "popped out" at me.
Didn't you resurect this car back to life a few years ago, with minimum engine work?

Fri Nov 29, 2013 12:29 am

Yes, I only detailed the engine. Before I took the engine out I checked to see if the head was loose and it was tight as can be but it may not have been seated properly.

Fri Nov 29, 2013 3:30 am

you will probably need to look at the engine case. The registers likely have sunk in the middle over time. Mag is soft and does that over many years.

that causes the head not to seat the cylinders flat.

Fri Nov 29, 2013 6:00 am

Clean and oil the stud threads. I'd even run all of the nuts down on them to make sure the head nuts go on nice and smooth, This might help in you not pulling a head stud when you reassemble them. Right now, that'll be your biggest worry, getting the heads to torque back up to spec. I think they're 23 ftlbs if I remember right.

Thu Dec 26, 2013 9:28 pm

Update:

Finally got the engine in and started the car. Sounds much nicer than before. Figure that the heads needed to be changed out.

Thu Dec 26, 2013 10:25 pm

glad it's running good

give it a couple heat cycles and check the head nuts. then do it again after 1500 miles.

I say this because I had this issue, the engine had been way overheated before, and they kept pulling. Russ helped me figure that one out.