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im on a highway to hell
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Discussion Starter · #1 ·
i have a 68 327 block with 70 heads, lower end is all stock and i have a comp cam (mild) edelbrock intake and carb early 80's hei dist. started the motor last summer and have been slowly rebuilding the rest of the car so it was never driven on the road until a few weeks ago it has maybe 2 hours total running time in the yard tuning and moving the car around and a trip to the alignment shop and the muffler shop maybe a total of 8 to 10 miles this whole time i have had no issues the motor runs strong, no leaks, and no ticking or knocking.

the other day when i returned from the muffler shop i thought i heard a noise from the motor yesterday i did hear a knock (not loud) and the oil pressure light came on i installed a mechanical gauge and nothing no oil in the tube (and no knock at restart) all of a sudden oil pressure is just gone:eek: the machinist who built the motor did tack the oil tube so it wouldn't fall off. any suggestions would be helpful. thank you.
 

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You might try a prelube tool that simulates the distributor housing and is turned by a drill to see if the pump is working correctly. You'll have to remove the distributor to use it.
The intermediate shaft that engauges the bottom of the dist. and the top of the oil pump may not have had enough engaugement with both and stripped or become disloged. The prelube tool can be a good test.
Have you changed the oil that was first installed for break-in? If not the filter may have become clogged from the moly additives in the break-in oil?
The oil filter bybass valve in the oil filter adapter should have let the oil pressure rise though.
Perhaps the oil pump is bad. The prelube tool would be a good test.
Might be able to borrow a pre-lube tool from Autozone? Spin it clockwise with the drill and have someone turn the key to "on" without turning it far enough to engauge the starter, and monitor the oil gauge.
FWIW
ssmonty
 

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im on a highway to hell
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688 Posts
Discussion Starter · #3 ·
took the dist.out i can feel resistance on the shaft when i turn it and i measured the distance from the shaft to the base of the intake there is about a 3/4 inch overlap so i believe the shaft was engauged properly.i'll check with az to see if the have a priming tool.

thanks for the help
 

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Get in, sit down, hang on
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...
Might be able to borrow a pre-lube tool from Autozone?
...
I work at a NAPA store here in Canada, and the expectation of "free" everything kind of floors me!

We have installers that buy $1,000's of dollars per month of parts from us.
I don't understand why a parts store would risk "biting the hand that feeds them" by enabling the guy that *might* buy something?

Yes, we used to bench-test an alternator or starter when we had our own shop and qualified technician ... for a fee. We would then waive that fee if the test results indicated that a replacement was needed, and that we got to make a sale.

We still do free battery load-tests to determine if the battery needs replacing (this takes about a minute or so) but no, we do NOT install batteries for nothing!

We have been also installing wiper blades for free (usually standing in the rain) but even that is getting to be a time-consuming process because of all the new attachment styles.

But yeah ... the free tool rental thing is the one that still amazes me. I had a customer come in looking for a tool because:
A.) "The Canadian Tire one was a POS"
B.) "Their mechanic had a GOOD one, but refused to sell it to me!"

Really? :confused:
Did you REALLY expect that they should have? :rolleyes:

I'm also going to repeat something that I said just a few days ago.
The best advice that I can give my customers is to stop asking parts people for mechanical advice.

Parts people SELL parts, mechanics (technicians) INSTALL parts.
Free advice is often worth less than what you paid for it.
 

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If you installed a mechanical oil gauge and oil did not flow through the tube, you either have a screen plugged or pump failure. Unless you want to rebuild the motor again you need to drop the oil pan and do some checking.
 

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Did you use an intermediate shaft with the nylon coupling? Combining these with high volume or high pressure pumps has been known to result in coupling failure.

PatM
 

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im on a highway to hell
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Discussion Starter · #7 ·
thank you all for your opinions and help. well i decided to sit down and think for a few minites and mull over everything that has happened in the last day or so and decided before i tore things down any further do keep it simple and start with the oil and filter so i drain the oil and it was dirty but i felt no grit at all in the oil took down the filter and it was heavy so it was full.slight gray tinge to the color but again i didn't feel any debris in the oil. now here's the kicker took the oil and put it into a gallon jug to dispose of it and if i was lucky there were only about 3 quarts in there!!!!! so i guess my dipstick is wrong i need to re mark it! so being down a couple quarts would make me loose oil pressure and the light would come on and the gauge would read zero. i put it all back together but i screwed up the mark on the dist. so i need to reset the timing at tdc and i didn't have the patience to do that today so i will set it on sat. and let you all know how a made out thanks again for the input!
 

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http://www.warsprints.com
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If the pickup tube is located to high from the bottom of the pan, being 2 quarts low may be an issue but if the tube is where it should be (3/8") from the pan bottom, it should not give you indications of "0" oil pressure. If you are using a Fram oil filter, CHANGE IT!!! Get a Wix, Purolator or any other "good" filter.
 

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The AMC, FORD, & CHEVY Guy??!!
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Rich, setting the timing back to TDC should be fairly straightforward without taking anything further apart.

*I'm assuming the spark plugs are still connected to the cap in the correct order.

1.) Hand crank the motor so the timing mark on the balancer lines up with the TDC mark on the balancer. Remember this does not mean we are on the compression stroke.

2.) Follow the #1 spark plug wire back to the distributor cap. Install your dizzy so that the rotor points to the #1 wire on the cap. Install cap.

3.) Attempt to start the engine. One of three should will happen:
a.) It starts. Horay! You got lucky (25% chance). If it stumbles/runs rough you just need to tweak the timing in.
b.) It backfires (25% chance). You are 180* off on the timing. Pull the dizzy and move the rotor so it points to the opposite direction from where it rests. Reinstall cap with the same orientation as last starting attempt. Repeat step 3.
c.) It does nothing but crank (50% chance) then reinstall the dizzy so the rotor points 90* to the left or right from where it rests. Reinstall cap with the same orientation as last starting attempt. Repeat step 3 (should now start or backfire).

If you do this a couple of times without success you will need to pull the LH valve cover so you can rotate the engine to TDC on the compression stroke. The #1 valves will both be closed when the timing mark on the balancer is lined up with the 0* mark on the cover on the compression stroke.
 

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NO OIL Pressure

First did you bleed the oil tube going back to your pressure guage? next check to see if the hole in the block is not stopped up. Then I would recommend measure the distance from the intake to the oil pump shaft slot and (I use a screw driver shaft on a drill) to spin the oil pump to check the oil pump itself. I know this sounds beginning 101 mechanics but some times it the easiest to start with. Hope this helps. Jessedenny47
 

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im on a highway to hell
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Discussion Starter · #12 ·
thanks novaman i can get the timing reset i was just real tiered and a bit cranky so thats usually when i mess things up i'll get it done saturday when i go back up there.

as for the dist. i did measure everything and its ok its not like i never had oil pressure all along its been fine i had to re adjust some of the rockers when i first got it running and those rockers made quite a mess w/o the cover on.

bleeding the oil line for the gauge was the only other thing i didnt know about. i basically had the line off the back of the gauge and still nothing.
 

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Hey Rich!

No oil pressure eh? Here are a few thing I would think of if I was troubleshooting my own mill:

First, do you know an actual PSI value of oil pressure that the car used to have? Maybe it just runs low at idle, many chevy motors do and its not an issue.

I would think if you were getting zero oil pressure you'd hear a hell of a racket from the lifters. I'm not clear on how long you had it running with the oil light on? Did you measure the distance from the pickup to the bottom of the pan? Are you using an aftermarket pan at all?

I would certainly try priming the pump with a priming tool. You can make one out of an old distributor if you want, grab one from a bone yard. Get a drill motor and hook it up, see how much oil pressure you're getting. Even with only 3 odd quarts in there, you should still have enough to keep pressure. If you're confident, run the mechanical gauge out under the cowl and pin it under your windshield wiper. See if you're losing pressure steadily or what's going on when you're driving with your full oil pan.

K
 

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im on a highway to hell
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688 Posts
Discussion Starter · #14 ·
thanks erik, i mounted the gauge and connected it and nothing came up into the tube as to how long it ran i heard a slight knock and saw the oil light on and shut it right off when we started it back up there was no noise from the motor and we let it run for about 3 or 4 min. checking the gauge then we shut it off and that's where we are now. its a stock pan and i haven't pulled it down yet i was going to try and start it one more time with the fresh oil and filter when i reset the timing, if i get nothing then i'll pull the pan

i still don't understand how it could just stop pumping all of a sudden. its so weird i can feel resistance on the shaft when i spin it with a screwdriver so it appears to be working mechanically. i don't think i'm ever going to get to drive this car:mad::mad:
 

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Did you spin the oil pump drive the correct way when priming? Dont laugh someone did this in front of me.

Is the oil pick up a pressed in one, it may have came off or not sealed. That would be a instant oil psi loss.

Even a bearing or bypass or screen would have some pressure.

Does the distributor sit high and need shims, could be the oil pump drive gear is not engauged.
 

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Well it sounds like he had pressure and then lost it. But spin, I think your idea remains. Some of those aftermarket distributor hold-down forks are just garbage and you can never get them to stay tight for more than a couple weeks at a time. Could be it loosened up and allowed the distributor to pop out of the oil pump drive slot momentarily.
 

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im on a highway to hell
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Discussion Starter · #17 ·
update

all right here we go,:( so i set the timing cranked it and nothing so i needed to drop the pan and pull the pump. when i pulled the pan off there was grey sediment at the bottom of the pan when i rub it between my thumb and finger it feels like sand but its finer than that i pulled the pump and took it apart i didnt see anything wrong with it but i did notice that the cover had swirl marks from the pump gears.

so i took the pump and the oil pan to the machinist that put the motor together he said the sediment felt like sand but other than that he wasnt sure what it was. he did say that he;s betting that it clogged the pump and thats what happened to the pressure. so now i have to tear down the motor and hot tank everything then mic everything. he did feel confident that with the limited run time at worse i'll probably need new bearings but everything else should be ok.

so although i really wanted to drive my car a few times before the winter i guess im on hold till the spring needless to say im really bummed out about it but i know it could have been worse

he asked me what i used for oil on my start up and i told him 10/40 he told me i should use a zinc break in suppliment with it next time, and that was an important step for initial start up. he also said i should use a straight 30 weight oil with it. i think i feel a good drunk coming on soon lol:drunk::pain:
 

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Get in, sit down, hang on
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All of that powdered metal came from somewhere. My bet is that you wiped the (flat-tapped) cam.

I feel your pain. Been there, done that.


If it's a flat-tappet cam, you really need to use a ZDDP additive, single valve-springs, etc... and follow the cam mfr's break-in directions to the letter.
This would include pre-lubing the engine thoroghly, ensuring that it fires up instantly, and varying your engine RPM in the range of 1500 to 2500 to ensure splash oiling.

There are LOTS of threads here on HR on this subject. Do a search for "ZDDP" or "break-in" or "camshaft failure" or "wiped lobe" and you'll see what I mean.
 

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Google "Tunnel Ram 406"
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Replace this intermediate shaft with this because the shaft is tapered to prevent binding so it will turn freely. The oil pressure went down to 0psi on my 406 and turn out the shaft was binding.

 

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JS-70
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Replace this intermediate shaft with this because the shaft is tapered to prevent binding so it will turn freely. The oil pressure went down to 0psi on my 406 and turn out the shaft was binding.
I dont understand what you mean "the shaft was binding" I would think if it was binding, you would break the shaft or strip the distributer gear.

Unless you mean it was hitting on the 400 crank throw?
 
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