Continuing problems...

[Carlspike]

I tore the heads off my 3.1 today and found another problem to deal with. One of the head bolts is broken off. It looks like they were re-used at least once and possibly even had an impact used on it. The only good thing is there is about an inch sticking up out of the block. I was going to try and double nut it and hope I get lucky. If that doesn't work does anybody else have an idea?

[sharkey]

if you can get 2 nuts on it, thats the best way. other ideas are to use a stud puller or slot the top of it with a hacksaw and use a screwdriver to remove it. but as i said, best thing is to double nut it.

[Carlspike]

Well I've been checking around town for 2 nuts to fit it and I've ran into another problem. I got 2 nuts that fit an intact head bolt thinking it would be the same as the broken one, but when I got home they didn't. I figured it was because the one bolt was stretched, but when I went looking for nuts that fit the broken bolt all I could find that kind of fit it was a 7/16 x 14 but the bolts are metric. Are these bolts some special application thread?

[RednBlack]

Craftsman makes a tool that works great for removing studs and such.

Or a good pair of vise grips and pentrating oil and some patience. If you have an inch sticking out, shouldn't be that hard.

[Carlspike]

I got it out! I couldn't find the correct nuts so I figured I'd cross thread em on there and that alone put enough force to loosen it up. I should have my valves replaced from the machine shop in a few days and the I'll start putting it back together, I'll probably have some questions when I do but is there anything I should look out for?

[Carlspike]

Well I got everything back together a couple of weeks ago and the engine ran great... for about 2 minutes. I gave it a little bit of throttle and I heard a couple of metallic noises and the engine quit.. no restart. I pulled the timing cover off and it turns out the metallic noises I heard were the camshaft bolt breaking off and the cam dowel breaking off again. Since then I've been waiting to use my friends compression gauge and borescope. I finally got them today and I couldn't see much with the scope (batteries were almost dead) so I started doing a compression check turning the engine over manually. By turning the crank over at different positions of the cam I got cylinders 1,3,4,5, and 6 to read compression. They each read about 30 PSI on one rotation by hand, I figured that wasn't too bad for turning it over by hand. My friend got some batteries for the scope and compared cylinder 2 to cylinder 4 and said that one valve in #2 looked like it wasn't seated properly..... looks like I have to pull the heads off again. So I'm really sick of fixing this car. My question is if the back 3 cylinders all had compression they should be ok shouldn't they? I know the front has to come off but I'd like to leave the rear one on if I can, but I also don't want to have to tear everything apart again because I was wrong. Has anybody dealt with this before?

[bszopi]

I would start to look into reasons why the cam bolt and dowl keep shearing. There has to be something major wrong to have that happen twice now.

[Carlspike]

The cam bolt hasn't broken twice, just the dowel. The first time I'm not exactly sure what happened but when I took off the timing cover the dowel was broken off and the cam bolt was really really tight. The only thing I can think of is that the bolt came loose the first time, which sheared off the cam dowel and once the dowel broke the cam sprocket spun and tightened the bolt back up. I guess the cam bolt must have gone through a lot of stress the first time so when I put it back in and put it under a little stress it broke off. I'm going to replace the cam, lifters, and cam bolt this time around. The cam and the crank both spin easy and I've got everything together right, Is there anything else that could cause a problem like this?

[ignoreance]

I wrote this a couple of days ago I wonder if you read it

http://60degreev6.com/showthread.php?t=35044&page=2

its a link to your first post I told you watch the timing chain .. also how tight did you do the lifters ???? did you make them to tight ?

I tried to warn you when that dowel pin breaks on the camshaft your better replace the camshaft. Get yourself a new timing set cam and lifters... Sorry to hear Bout the breaking twice

[Carlspike]

The timing chain was replaced, that was the first thing I did. There is no adjustment for the lifters/rocker arms, you just tighten them to a torque spec. The reason I didn't replace the cam the first time is the engine is still in the car... and I'm working outside in the cold without an engine hoist. I don't really have any way to even pull the engine. I did drill out the old dowel and replace it with a new GM one. From what I'd heard the dowel is just for alingment, the bolt holds all the force so I didn't worry about it too much. It's gonna be a little long buty here is the whole story. I was driving down the road an the car started to run pretty bad, especially under load. Then all the sudden I heard a tapping noise and the car quit. I got it towed back home and figured the timing chain had jumped, it wasn't perfectly in time when I pulled it apart so I pulled off the front cover and took off the chain and sprockets. That is when I found the cam dowel had broken off. When looking at the old sprocket I could see that it spun on the cam. The cam bolt wasn't broken off, in fact it was incredibly tight. I got all that squared away and then got started on the heads. I got 7 bent valves replaced and had a valve job done on the rest and got the heads resurfaced too. I did the heads and after it was back together it ran for 2 mins and quit. Then I did all the checks that I mentioned in my previous post. Seems I have 2 more bent valves and now I definently need a new cam. I guess the cam bolt must have gotten stressed from whatever happened before. So thats where I am. I wasn't trying to skimp on the job, I just didn't think the cam bolt would have been that weakened by whatever happened the first time it broke. I'm about to start pulling it apart again, so my main question is: Should the cranking the engine by hand compression check I did be good enough to rule out bent valves? If I had belt valves in any cylinder but #2 (which has no compression) I shouldn't get any compression at all right?

[ignoreance]

You have a compression guage? If so measure all compressions. They should be all within about a 10-15psi range from each other. If they arn't there is probably a problem. Assuming your bottem half or block side is fine then there is a problem with the heads. Also when you do the compression check do any of them loose pressure quickly? best way to check your compression remove all rocker arms so that springs are closed take all your spark plugs out and then compression check each cylinder. That will tell you if the valve is sealing the springs will all be closed on every port. Thats the easiest way I can tell you to check it and I recomend taking a measure of three times then average them all should be again with in 10-15psi. I wish I could tell you what your psi should be but I haven't ever had to run a compression check on my motor yet. Maybe somebody else can tell you what it should be


It sucks having to work out side in the weather probably I don't have it as bad as you as I live in california where harsh weather is windy. It may dip below 32 about 20 days out of the year but if your back east I feel you cus I can remeber wrenching on my car in alaska that sucked.

[Carlspike]

I took the intake off and the #2 cylinder exhaust pushrod was bent. So I have at least 1 bent valve in there. Since I have to take the front head off I'm just going to the back one at the same time. I'll take them to a machine shop and have all the valves checked just to be sure. Do you know where I could get a reasonably priced cam and lifter set? Wrenching outside here does suck, at least it hasn't been too bad lately. Usually this time of the year it's 20's or less, but it's been hanging around 30.

[ignoreance]

Summit sells kits lifters and camshaft

http://store.summitracing.com/partdetail.asp?part=CRN%2D254122&N=700+4294908216+115&autoview=sku

Thats probably a light upgrade over stock but I'm not sure what they put in your motor to start with I wouldn't think you would have to change the springs and it ships tomorrow they have some other ones but might require different springs

[Carlspike]

That cam is a flat tappet, my car has a roller. I found a stock roller regrind from delta cams for 85+ shipping. I don't have the lifters and cam out yet so I'm gonna try to do that tomorrow. I wanna check out the lifters and cam bearings before I order anything.

[Carlspike]

Well, after all the headaches I think my engine is toast. I tried to pull out the intake lifter for cylinder #5 but it was really stuck in there. I finally got it out but the bottom part of it was broken off, so I shined a light down in the cam valley and found one of my cam bearings was wiped. I'm not sure if it's even worth to fix it now, since when the cam bearing spun it could very well have scuffed the block up pretty bad. I'm most likely going to part it out, is anybody looking to do a gen III top end swap?

I've posted a few pictures in the gallery http://60degreev6.com/gallery/browseimages.php?c=7