340 issue after camshaft change

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I’m back to head scratching. After using RustyRatRod’s method to adjust the valves, I felt pretty confident that it was done as close to right to at least get the engine running and break in the camshaft. It sputtered and backfired at first but I did get it running. It would not stay running on its own without keeping the gas pedal partly depressed. I played with the distributor a bit looking for the sweet spot to get it to at least idle. That did not happen.
Back to the beginning to ensure I had the distributor in correctly. Remove spark plug number one and crank the engine looking for the compression stroke. What do you know, no compression in cylinder number one. Put the compression tester on it and confirmed no compression in that cylinder. Rotated engine to what’s suppose to be #1 TDC and valves are closed.
I don’t want to make this too long winded but I’ve been a mechanic for a long time and have never encountered anything like this. I am convinced this camshaft is ground wrong! It’s coming out. I had a perfectly fine running car until this swap. I’m done with this cam, period.
So, with that said, I’m looking for suggestion for a nice street camshaft. I’d like some lope and am not concerned about gas mileage. Also, not looking to make it un streetable. What are some good camshaft suggestions?
 
You don't let a fresh build idle on initial start. It needs to run between 2500-4000 varying to get good oil splash to the camshaft for about 15 solid minutes. Letting one idle on initial start is a sure fire way to wipe a lobe on the camshaft, resulting in having to tear the engine down, clean all of the metal out, possibly replace ruined engine bearings and do it all again.
 
If the valves are closed on #1 TDC, there will be compression on #1.
The only way there wouldn't be is if there are no rings on the piston.
Are you sure the engine is firing on the proper cylinder ?
 
RustyRatRod said:
You don't let a fresh build idle on initial start. It needs to run between 2500-4000 varying to get good oil splash to the camshaft for about 15 solid minutes. Letting one idle on initial start is a sure fire way to wipe a lobe on the camshaft, resulting in having to tear the engine down, clean all of the metal out, possibly replace ruined engine bearings and do it all again.
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Yes, I know this!

fishmens67 said:
If the valves are closed on #1 TDC, there will be compression on #1.
The only way there wouldn't be is if there are no rings on the piston.
Are you sure the engine is firing on the proper cylinder ?
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Well, not 100% as I don’t have compression on #1 cylinder. It’s a big zero with the compression tester.

I’m done with this particular camshaft. There has to be something mechanically wrong with it. I will be pulling it out and putting it in the scrap bin. I’ve wasted enough time on it that I’m done. So, back to my question on a replacement cam?
 
Sabremech said:
I’m back to head scratching. After using RustyRatRod’s method to adjust the valves, I felt pretty confident that it was done as close to right to at least get the engine running and break in the camshaft. It sputtered and backfired at first but I did get it running. It would not stay running on its own without keeping the gas pedal partly depressed. I played with the distributor a bit looking for the sweet spot to get it to at least idle. That did not happen.
Back to the beginning to ensure I had the distributor in correctly. Remove spark plug number one and crank the engine looking for the compression stroke. What do you know, no compression in cylinder number one. Put the compression tester on it and confirmed no compression in that cylinder. Rotated engine to what’s suppose to be #1 TDC and valves are closed.
I don’t want to make this too long winded but I’ve been a mechanic for a long time and have never encountered anything like this. I am convinced this camshaft is ground wrong! It’s coming out. I had a perfectly fine running car until this swap. I’m done with this cam, period.
So, with that said, I’m looking for suggestion for a nice street camshaft. I’d like some lope and am not concerned about gas mileage. Also, not looking to make it un streetable. What are some good camshaft suggestions?
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Can u explain to us exactly how u adjusted the preload? Did u pump up the lifters with oil? U got to be missing something. We want to help u!!! Don’t give up yet. Kim
 
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Is it a reverse direction cam for a boat ?
 
oldkimmer said:
Can u explain to us exactly how u adjusted the preload? Did u pump up the lifters with oil? U got to be missing something. We want to help u!!! Kim
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No, per comp cams instructions, pumping them up is not required. I understand the help and appreciate it. I’m convinced this camshaft is bad from the manufacturer. It is coming out. Like I posted earlier, I’m not putting any more time in troubleshooting it.
I’d appreciate some suggestions on a different street camshaft with a little lope to it. Thanks.
 
Sabremech said:
No, per comp cams instructions, pumping them up is not required. I understand the help and appreciate it. I’m convinced this camshaft is bad from the manufacturer. It is coming out. Like I posted earlier, I’m not putting any more time in troubleshooting it.
I’d appreciate some suggestions on a different street camshaft with a little lope to it. Thanks.
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Can u post their instructions? Did u degree the cam? Thanks. Kim
 
oldkimmer said:
Can u post their instructions? Did u degree the cam? Thanks. Kim
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Appreciate the help. As posted here by another member, the instructions do not require the lifters to be pumped up. I did not degree the cam. There’s no adjustment capability so what good would degreeing it do?
This is my last post in regards to this particular camshaft. I’m done with it.
So, not trying to be a jerk, but any other camshaft suggestions? Thanks.
 
Sabremech said:
Appreciate the help. As posted here by another member, the instructions do not require the lifters to be pumped up. I did not degree the cam. There’s no adjustment capability so what good would degreeing it do?
This is my last post in regards to this particular camshaft. I’m done with it.
So, not trying to be a jerk, but any other camshaft suggestions? Thanks.
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With offset woodruff keys your cam install is adjustable. But it sounds like you have mind set on another cam. If you do get another cam, let me know how much you want for this one.
 
Sabremech said:
Yes, I know this!



Well, not 100% as I don’t have compression on #1 cylinder. It’s a big zero with the compression tester.

I’m done with this particular camshaft. There has to be something mechanically wrong with it. I will be pulling it out and putting it in the scrap bin. I’ve wasted enough time on it that I’m done. So, back to my question on a replacement cam?
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Well send me that cam instead of scrapping it. I’ll make it work for me. Thanks. Kim
 
Sabremech said:
I’m convinced this camshaft is bad from the manufacturer. It is coming out.
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By bad, what specifically do you mean? Ideally before settling on the cam being at fault, wouldn’t it be worth it to partially disassemble down to where you can check and verify everything you have done is correct, and if that all checks out then move on to ultimately diagnosing where the problem lies with the cam? Yanking and slinging it may give some gratification (I like smashing defective things but that’s just me:eek:) but how can you be sure it in fact is the issue without first verifying everything? Find the actual fault/issue first regardless, then perhaps “sling” :thumbsup:
 
I think it's a mistake just replacing the camshaft without finding 100% sure WHY you're having issues with it. ...and I'm not bein smart here, but what if it's an error on your part somewhere? Without verifying 100% what the problem is, you're setting yourself up for a repeat performance.
 
Sabremech said:
Appreciate the help. As posted here by another member, the instructions do not require the lifters to be pumped up. I did not degree the cam. There’s no adjustment capability so what good would degreeing it do?
This is my last post in regards to this particular camshaft. I’m done with it.
So, not trying to be a jerk, but any other camshaft suggestions? Thanks.
Click to expand...
. Not Comp
 
Don't be so quick to condemn this. How have you "made certain" the valves are closing? One way is a leak down test, and along with that is visually cycling the valves. Crank til one valve FULLY opens, then visually turn the crank ONE TURN. This will put the lifter "for damn certain" on the heel of the cam. See that the valve lash is "loose" and that the valve IS CLOSED If you don't have a leakdown tester, at least visually cycle the valves both closed and pressurize the cylinder at that TDC and listen for air out the intake, exhaust, or cooling system.

Having said that we DID have one member on here (273 I think) got ahold of a marine counter rotation cam
 
RustyRatRod said:
I think it's a mistake just replacing the camshaft without finding 100% sure WHY you're having issues with it. ...and I'm not bein smart here, but what if it's an error on your part somewhere? Without verifying 100% what the problem is, you're setting yourself up for a repeat performance.[/QUOTE. I don’t see why he wouldn’t verify what the problem is. Jumping to conclusions is not the way to do it. But I guess it’s his time and money. Good chance he caused other problems. Kim
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Sabremech said:
Appreciate the help. As posted here by another member, the instructions do not require the lifters to be pumped up. I did not degree the cam. There’s no adjustment capability so what good would degreeing it do?
This is my last post in regards to this particular camshaft. I’m done with it.
So, not trying to be a jerk, but any other camshaft suggestions? Thanks.
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Put the original camshaft back in and be happy.
When you swapped cams did you change the timing chain and gears?
 
Reading this horror story has got me all freaked out. I'm in the middle of the same job with my 340. New Oregon Camshaft, lifters and timing chain are installed. Waiting on Smith Brothers pushrods which should arrive tomorrow. Should get my car back together over the weekend with much better results although its my first time doing a new cam and lifters.
 
gtgto said:
Reading this horror story has got me all freaked out. I'm in the middle of the same job with my 340. New Oregon Camshaft, lifters and timing chain are installed. Waiting on Smith Brothers pushrods which should arrive tomorrow. Should get my car back together over the weekend with much better results although its my first time doing a new cam and lifters.
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A methodical approach does wonders. You really SHOULD degree the cam, and many of us runnig lower compression (9.5 and less) engines usually benefit by advancing the cam timing by means of a multi-key sprocket set or other means. I had a friend over here due to what the engine "wanted" and the fact that something was a bit off, maybe the cam ground off, we advanced the thing 6 or 8 degrees. It went from a dog to a "scalded dog". This was in a pickup, so it needed more mid range torque.
 
gtgto said:
Reading this horror story has got me all freaked out. I'm in the middle of the same job with my 340. New Oregon Camshaft, lifters and timing chain are installed. Waiting on Smith Brothers pushrods which should arrive tomorrow. Should get my car back together over the weekend with much better results although its my first time doing a new cam and lifters.
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Word of advice, degree the cam so you know what it is installed at.
 
You don't have to pump up hydrualic lifters but as Kim stated, Instead of turning the puhsrod to feel for zero lash, you move the pushrod up and down until there's zero lash then set preload .
I put hydraulics in my old Harley and you install with no oil and slowly screw in until the lifter is bottomed out and then back out a turn. Totally different concept. (Not For Cars)
 
RustyRatRod said:
I think it's a mistake just replacing the camshaft without finding 100% sure WHY you're having issues with it. ...and I'm not bein smart here, but what if it's an error on your part somewhere? Without verifying 100% what the problem is, you're setting yourself up for a repeat performance.
Click to expand...

I’ve had the engine apart 3 times now verifying installation. I’ve done valve adjustment 4 times now. I’ve verified that I’m not 180 degrees off as many times now. I’ve drained antifreeze 3 times now and will be disassembling it for the 4 th time in the future. I did not find anything glaringly wrong any time I had it back apart.
This engine should at least run ok without degreeing it. It doesn’t.
I do not have it in me to continue to troubleshoot this camshaft any longer. What’s wrong with it? I don’t know but I suspect it’s ground wrong or maybe it’s a marine camshaft and ended up in a auto box. I no longer believe this is an installation issue but a manufacturing issue.
The car is up on my lift with the cover on and I’m walking away from it for a while. When I get over the disgust, I’ll take it back apart and remove this camshaft and install a different one.
Thanks much
 
That really sucks. Cal the manufacturer of the cam with the number and tel them the issue.
 
Sabremech said:
I’ve had the engine apart 3 times now verifying installation. I’ve done valve adjustment 4 times now. I’ve verified that I’m not 180 degrees off as many times now. I’ve drained antifreeze 3 times now and will be disassembling it for the 4 th time in the future. I did not find anything glaringly wrong any time I had it back apart.
This engine should at least run ok without degreeing it. It doesn’t.
I do not have it in me to continue to troubleshoot this camshaft any longer. What’s wrong with it? I don’t know but I suspect it’s ground wrong or maybe it’s a marine camshaft and ended up in a auto box. I no longer believe this is an installation issue but a manufacturing issue.
The car is up on my lift with the cover on and I’m walking away from it for a while. When I get over the disgust, I’ll take it back apart and remove this camshaft and install a different one.
Thanks much
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If you can post particulars such as static compression, induction, exhaust, converter and gear, Ill be glad to help with a recommendation. ...and what engine again?
 
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