Help me diagnose this noise
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
I called Thunder Racing, and they said that the pin is necessary. They recommended that I pull the cam, replace the pin, and reinstall it. I'm going to speak with one of their techs later to get specifics on why this will be necessary because I'm not doing it without a damn good reason.
I am inclined to go home, put the bolts through the timing gear, check to see if there is any play or if they are tight, and if they're tight I'll put the damn thing back on tonight and go racing this weekend. If there is play, I'll heed their advice.
Anyone want to weigh in on this?
I am inclined to go home, put the bolts through the timing gear, check to see if there is any play or if they are tight, and if they're tight I'll put the damn thing back on tonight and go racing this weekend. If there is play, I'll heed their advice.
Anyone want to weigh in on this?
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
Here is what I found out from Thunder Racing...
- The pin is necessary.
- The bolts have play but the pin fits snugly into the hole in the timing gear.
- The pin is pressed in with a large hammer.
- They advise against trying to press the pin in while the cam is in the engine.
- The hole for the pin may have been rounded out by what has happened and the cam may be fucked.
Here's my plan currently... My father works at a University, and he is friends with a machinist there. I'm going to bring him the bolts and the timing gear and see if he can make me some sleeves to go around the bolts to eliminate any play. The only down side is that this guy can only make them out of aluminum. I'm not sure that'd be strong enough. However, with the head of the bolt crushing it down where would the aluminum have to go if it started to get out of shape?
Anyway, that's what's going on. I'm still keenly interested in your opinions.
- The pin is necessary.
- The bolts have play but the pin fits snugly into the hole in the timing gear.
- The pin is pressed in with a large hammer.
- They advise against trying to press the pin in while the cam is in the engine.
- The hole for the pin may have been rounded out by what has happened and the cam may be fucked.
Here's my plan currently... My father works at a University, and he is friends with a machinist there. I'm going to bring him the bolts and the timing gear and see if he can make me some sleeves to go around the bolts to eliminate any play. The only down side is that this guy can only make them out of aluminum. I'm not sure that'd be strong enough. However, with the head of the bolt crushing it down where would the aluminum have to go if it started to get out of shape?
Anyway, that's what's going on. I'm still keenly interested in your opinions.
I would think youd be way better off just tapping the pin back in. The threads on teh three bolts will pressinto aluminum pretty easily and any play the sleeves took out with now be reintroduced.
If youre worried about the pin falling out again, you coulf simply used something to line up the pin hole w/ the cam sprocket hole while you tighten the bolts up. Once theyre tight, it should stay aligned unless they loosen up again.
I still think presing the pin back in is teh best way to go about it though... Maybe some loctite or other epoxy would hold the pin in there if theres not enough friction to hold it on dry.
If youre worried about the pin falling out again, you coulf simply used something to line up the pin hole w/ the cam sprocket hole while you tighten the bolts up. Once theyre tight, it should stay aligned unless they loosen up again.
I still think presing the pin back in is teh best way to go about it though... Maybe some loctite or other epoxy would hold the pin in there if theres not enough friction to hold it on dry.
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
Yes, but do you think it can be pressed in without pulling the cam? I am sick to death of taking this ******* engine apart at this point. If I can do anything to keep from pulling this cam, I will.
I'm wondering if there's anywhere I can look to get the sleeves made out of steel. I think the sleeves are the best ultimate solution.
I'm wondering if there's anywhere I can look to get the sleeves made out of steel. I think the sleeves are the best ultimate solution.
Originally Posted by Gauge
Yes, but do you think it can be pressed in without pulling the cam? I am sick to death of taking this ******* engine apart at this point. If I can do anything to keep from pulling this cam, I will.
I'm wondering if there's anywhere I can look to get the sleeves made out of steel. I think the sleeves are the best ultimate solution.
I'm wondering if there's anywhere I can look to get the sleeves made out of steel. I think the sleeves are the best ultimate solution.
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
My father took the stock cam, gear, and bolts to a machinist today. The machinist is going to use brass to put shoulders on the bolts. This should eliminate the need for the pin. If it doesn't work out, I've got a pin on the way from Thunder Racing, and I'll just have to pull the cam again.
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
It turns out that the machinist couldn't make the shoulders for the bolts because the bolts are metric and he can only make standard threads. Looks like the cam will be coming out tonight! 
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Verdad Gallardo Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
Originally Posted by GuitsBoy
With teh front cover off, pulling the cam should take less than half an hour. All you need to do is pull the rockers and pushrods, no???
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
I believe this is the end of this thread...
Tonight a buddy and I pulled the cam. We were excited at how easy it was for us the second time around. We go the thing out in like 90 minutes. I hammered the new pin in and got it exactly as far in as the stocker was. I got the bolt holes all cleaned up and got ready to oil the cam to put it back in the motor.
I then realized that the cam was scarred really bad, so it was worthless. I noticed that the lobe for the intake on #2 was one of the screwed up lobes. I stuck my finger in the front of the engine and felt that lifter. Not only was it scarred, but the roller was flattened at one point. The brand new lifters were obviously hosed.
I thought I'd have to take the damn heads off again, replace the lifters again, and then replace the cam. I then thought to look at the cam bearings. The front cam bearing is scarred up really badly. I'm under the assumption at this point that the engine needs to be pulled and rebuilt. If that's the case, then I will wait until I have the money for a 408. At this point, my monetary resources are depleated as are my patience.
Sorry, baby. You're going to be in the garage for a while. I'll have a few drinks for you while you're on hiatus.
Tonight a buddy and I pulled the cam. We were excited at how easy it was for us the second time around. We go the thing out in like 90 minutes. I hammered the new pin in and got it exactly as far in as the stocker was. I got the bolt holes all cleaned up and got ready to oil the cam to put it back in the motor.
I then realized that the cam was scarred really bad, so it was worthless. I noticed that the lobe for the intake on #2 was one of the screwed up lobes. I stuck my finger in the front of the engine and felt that lifter. Not only was it scarred, but the roller was flattened at one point. The brand new lifters were obviously hosed.
I thought I'd have to take the damn heads off again, replace the lifters again, and then replace the cam. I then thought to look at the cam bearings. The front cam bearing is scarred up really badly. I'm under the assumption at this point that the engine needs to be pulled and rebuilt. If that's the case, then I will wait until I have the money for a 408. At this point, my monetary resources are depleated as are my patience.
Sorry, baby. You're going to be in the garage for a while. I'll have a few drinks for you while you're on hiatus.
Can you grab some pics of the cam bearing? The front cam bearing is notorious for looking like its worn even when its well within spec. Sorry to hear about all the bad luck. but please, dont call me 'baby'. Seriously man, you cant stop here. Give her a few days to cool off, but atleast now you know what was wrong. No more guessing if the valve tim would make the ticking.
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
Here's a pic of the front cam bearing. Let me know if you need something better. Just FYI, when I run my fingernail across it it catches several times and does not run smoothly across it.
Here are some pics of the cam lobes just for fun...
Here are some pics of the cam lobes just for fun...
Oh man! That does look rather gnarly. If its just the first cam bearing, those can be replaced with the block in the car, however for any of the other ones behind it, youll have to pull the block. That cam is seriously toast. And like you said, theres a good chance the lifters are as well. You said one had an actual flatspot already? How long were you running the motor after you got it reassembled? **** **** **** **** ****.
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
Originally Posted by GuitsBoy
And like you said, theres a good chance the lifters are as well. You said one had an actual flatspot already? How long were you running the motor after you got it reassembled? **** **** **** **** ****.
Thread Starter
Joined: Dec 2004
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From: Dallas (Richardson), TX, USA
Just as an update. Here is one of the lifters that I pulled. Most of them looked pretty good, but some were screwed up, and this one was absolutely hosed beyond imagination. I thought this was post-worthy even for those who didn't follow what was going on.