07GTIMYFAST

No oil flow in head

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I was having problems with hot start situations and the engine turning over really slow when warmed up to operating temp. First I unplugged the coil to make sure the timing wasn't the issue, then double checked the carb to make sure it wasn't "hot flooding".

I then removed the oil filler because I also heard a "rattle" at random times like a heat shield but upon further investigation it sounds like chain slap from the timing chain. So when i removed the oil filler to try to narrow the sound to inside the head, I was expecting oil to be flying or atleast see it flowing thru the head (like I have seen it do before while running) But no dice, just alittle splatter every now and then.

The oil pressure light works and is not indicating a loss in oil pressure but I'm at a loss at why no oil is flowing thru the head. Could the oil channel in the rocker shaft be clogged?

this is a high mileage spare engine I took from my 1974 parts car I don't know if the engine was ever rebuilt but it has atleast 200k+ on the engine

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Guest Anonymous

I guess it's possible that oil is not getting sprayed from the oil spray bar or the rocker shaft end caps have come off. You need to remove the valve cover to check both. Disconnect the coil wire, crank the engine to see if oil is getting to the spray bar which sits above the cam and check the rocker arm shafts at the front to see if the plugs are still in the ends and/or if oil is leaking from the ends. This has been a common problem.

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thanks for the advise, I will be checking that this morning. what is the solution to that common problem usually? If it doesn't come out of the bar I will remove it and repeat to see if oil comes thru the oiler bolt.

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Slow idle compared with high mileage motor - I think the pressure may be so low at idle that the flow is minimal like you described. Pressure switch operates at even lower level. Give it some revs and see if flow increases.

Tommy

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sorry I should have mentioned I tried that aswell originally, reved it up a couple times to around 4k-ish still with no oil flow

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Hmmm - that sounds more concerning. Checking those end plugs is one thing to do. Also measuring the pressure with an analog gauge would give info. The tiny holes on the spray bar can be clogged easily.

Tommy

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I will definatly be checking the plugs and bar this morning, I don't have a gauge but if there is no oil flowing I will move from there. Does anyone have a link to buy those plugs on hand? I beleive they are little lead plugs if my memory serves me.

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STOP!! - buy a OIL PRESSURE TEST GAUGE

....yer just swatting at the flys

OIL PRESSURE TEST GAUGE

without first knowing the output

of the oil pump - yer just wasting

time

FUEL PRESSURE TEST GAUGE

without knowing the fuel pressure,

and output/volume in 30 seconds

into a measuring cup - yer just banging

yer head and knuckles

COMPRESSION TESTER

with low compression -

yer motor is not a motor

VOLT/OHM/MULTIMETER

another time saver and guess

eliminator

...your looking for min. 125psi... 140psi at COLD start 1500 rpm

.......................... min. 14psi... 20psi at HOT idle

..................... approx. 45psi.... 75psi at HOT 4500 rpm

the test gauge needle should be steady,

not swinging back and forth over a 10,,,,20+psi reading

M10oilpumpparts02.jpg

02oilboltandfilter.jpg

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...your looking for min. 125psi... 140psi at COLD start 1500 rpm

.......................... min. 14psi... 20psi at HOT idle

..................... approx. 45psi.... 75psi at HOT 4500 rpm

no, you're not.

Cold, with a fully functional oil bypass valve, you could see as high as

90 with 15-50. But usually, it will idle around 60, jumping to 80 or

90 when you accellerate.

If it goes much over 100 psi, good chance you have a sticky bypass.

Hot idle, 15 is lame, 30 is good. In- between is normal

Hot at 2000+ the current regulators are trying to hold 55-60 psi.

Much over is regulator trouble, much under is bigger trouble.

And what you usually see when you take the cap off running is a fine mist-

very little liquid oil.

However, if you leave it off for any length of time, an oil haze gets

all over everything, including your windshield.

I'd take the cover off and check things. A pressure gauge is a good diagnostic

of top- end trouble- popped end plugs give you zero.

Found that out in a hurry one morning.

t

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I'm not going to buy a bunch of tools for a engine that I could really care less if it goes out or not haha. Thanks for the heads up tho. I pulled the valve cover and turned the engine over, no oil flow to the head but when I connected the coil and and cranked it up without the valve cover on oil was squirting from the bar onto the cam lobes from the bar, so as for oil starvation issues I'm not to worried, also oil flew everywhere haha, but I was expecting that.

I fooled around with the timing and webber a bit and got it to where it will fire up on hot start but it still turns over slow. I backed the timing off so it pops off with very little starting RPM. It smokes on startup which I'm sure is leaky valve seals. Still trying to work out the webber mystery issue,

between idle and 1/4-1/2 throttle it spits and sputters , but if you pull the choke all the way out it runs perfectly. My only guess is either 1 its running lean on the idle circuit (which I have adjusted to no avail) or 2 the vacuum is not enough. I have a small Vac leak at the brake booster but don't know if it would cause that big of a issue.

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