Vibrating oil gauge

jermmdogg

Member
The problem I'm having is when the oil warms up. The needle on the mechanical gauge will vibrate so bad, the needle is invisible. I've replaced the oil pump twice. Replaced the distributor. By passed the oil filter. By passed the oil cooler. Plugged the oil inlet and ran the oil filter right on the block. Moved the oil pressure line for the gauge from the front to the back of the block. Just recently pulled the timing cover expecting to see a lose cam gear. Everything looked ok. The wear pattern on the distributor gear looks good. I'm going to send in the damper and have it rebuilt. I don't really think that going to help any. The only thing I've done different from the many Clevor engines I built was I used a Dart sportsman block. Witch has priority main oiling.
I just put together a Dart Ford 351 sportsman block with PowerPort Cleveland 225 cylinder heads. The rotating assembly is a Scat 3.85 stroker with Cleveland mains and Chevy rod journals, 6.200 H-beam rod with Racetech pistons. The cam is a hydraulic roller with oem style lifters. The oiling system is a seven quart pan with a melling high pressure pump still driven off the distributor. It has e remote oil filter and cooler, all ran with #10 line. It has a double roller timing chain and a ATI damper steel hub aluminum housing. It has a TKO transmission behind it with 164 aluminum flywheel and a Mcleod dual clutch. Running a true10w-30 synthetic oil. Red Line or Royal Purple.
 

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I have to assume its a mechanical gauge with an oil line directly attached to the engine
It could have air in the line and needs to be bled. Loosen the fitting on the back of the gage to let some oil run through. This can be done with the engine running or take out the top spark plug wire connections and spin it with the starter. Don't forget a rag and to tighten the fitting when done.
 

jermmdogg

Member
Yes, mechanical. I give that a shot. So, the oil pulsating isn't really an issue? I see all the parts moving in my head and fear the worst.
 

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
You might just have an air bubble in the oil pressure gauge line
 

jermmdogg

Member
So there wasn't much air in the line. It actually seemed to make it worst. So I blew the oil out of the line and tried it. The air damped the vibration. But it still does it. The vibration is not constant through the rpms. It also doesn't do it at certain rpm. It kinda seems like it does it more under decell. But I think that's just me seeing something that isn't there. The one constant thing is, as the oil get hotter. The more the needle vibrates. When the oil is cold. The needle will be almost steady. I can't tell you how many times I thought I figured it out, and it was just that the oil was cool. This isn't the actual gauge, but this is exactly what it looks like.
I'm going to pull all the rockers and make sure the cam turns freely.
 

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jermmdogg

Member
Just some more info. I've put 4,500 miles on it and there hasn't been a failure. The valve train sounds normal. The valve adjust is a half turn. The normal 1/4 turn plus another 1/4 for the aluminum heads.
 

jermmdogg

Member
So I pulled the the rockers and timing chain. Cam and everything turned freely. I did find that the chain would snap into about half the teeth on the cam gear. Like a lego. Ordered a new timing set. Not saying this is the problem. But I'm crossing my fingers.
Has anyone ran across this before?
 

jermmdogg

Member
So I got it back together finally. The timing set fixed it. It was a JP performance billet dual roller timing chain. I replaced it with a Compcam one. From what I can find, they are a German company. Not saying they make bad products, but I'll probably never use them again.
 

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
although it has not a thing to do with this particular deal, I would point out that decades ago I purchased a SBC timing gear chain set that was on sale in a NAPA store in one of those deals where they have loose inventory stacked in a large table with a sign that said pick any one item for $19.99 or any 6 for $99.99
in fine print on the back it said made in india.
well I used it (or tried to) on a stock 307 SBC rebuild, when degreeing the cam in I found the DOT-TO-DOT marks would in fact place the cam 11 degrees advanced.
I stuck to buying CLOYES timing chains or gear drives ever since


http://garage.grumpysperformance.com/index.php?threads/cam-drive-details.3809/#post-16765

http://garage.grumpysperformance.co...hanics-of-adv-ret-a-camshaft.4532/#post-12048


http://garage.grumpysperformance.co...-get-it-to-last-cam-install-info.90/#post-114
 

jermmdogg

Member
It does have to do with this particular deal. I was trying to save money and as usual. It cost me more in the long run.
 
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