timinggears woes/another question
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timinggears woes/another question
i posted not to long ago about my 88 250 300 , with bad timing gear , fix it and ran real ruff and low compression.
update: compression ok not great the gauge was broke still runs very ruff.
question: took off valve cover when spinning engine over no oil comes out of the push rods or rockers when engine running it had oil pressure? could the oil pump be bad or be blocked causing little or no oil to flow to the lifters causing the the valves not to open and close like they should making the engine run ruff?
update: compression ok not great the gauge was broke still runs very ruff.
question: took off valve cover when spinning engine over no oil comes out of the push rods or rockers when engine running it had oil pressure? could the oil pump be bad or be blocked causing little or no oil to flow to the lifters causing the the valves not to open and close like they should making the engine run ruff?
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From: Colorado
Assuming you were able to align the marks on the timing gears, there could be many other reasons for rough running.
I don't know if you posted how many miles you have on the engine, but one of the problems with the long lived 300 is that the oil pumps do eventually fade. Did you see evidence that oil HAD been circulating up through the rockers? Perhaps it had been but the pump is just weak enough to only oil while the engine is running. I can run my carb'd 300 with the cover off, so I've never checked to see if oill comes up with a crank spin only.
'88 F250 should be fuel injected, so it's a PITA to reassemble & run the engine with the cover off - but if there's oil in and around the rockers, you probably just aren't seeing it with a starter spin of the engine.
If you aren't getting oil up through the rockers, I'd expect squeaking and damage to occur rather rapidly. What kind of pressure is your oil gauge showing?
Broncr
I don't know if you posted how many miles you have on the engine, but one of the problems with the long lived 300 is that the oil pumps do eventually fade. Did you see evidence that oil HAD been circulating up through the rockers? Perhaps it had been but the pump is just weak enough to only oil while the engine is running. I can run my carb'd 300 with the cover off, so I've never checked to see if oill comes up with a crank spin only.
'88 F250 should be fuel injected, so it's a PITA to reassemble & run the engine with the cover off - but if there's oil in and around the rockers, you probably just aren't seeing it with a starter spin of the engine.
If you aren't getting oil up through the rockers, I'd expect squeaking and damage to occur rather rapidly. What kind of pressure is your oil gauge showing?
Broncr
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more info
the truck has about 189k on it ran great until big gear went bad , oil pressure on gauge is in the middle timing should be right both keyways are in the 12'oclock and the dots are matching . The day i went on my trip the engine sounded funny like a slight knock like it wasnt getting enough oil in engine (oil pressure still good then) but i went on my trip anyway and broke down 2 hours away from home. i thought maybe the oil pickup could be blocked with debri or pump failure??
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From: Colorado
Well, that's certainly a possibility. Unfortunately, there's only one good way to find out , you need to tear into it and see what you find. Unless, of course, you can get it running again.
Do you have the coded diagnostics (check engine light)? It may be possible to retrieve some info from that. I'm not sure but I believe that '88's have the self diagnostics IIRC.
Broncr
Do you have the coded diagnostics (check engine light)? It may be possible to retrieve some info from that. I'm not sure but I believe that '88's have the self diagnostics IIRC.
Broncr
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From: Houston TX
could the oil pump be bad or be blocked causing little or no oil to flow to the lifters causing the the valves not to open and close like they should making the engine run ruff?
Dunno..If it is, you will know it. The engine should be clacking like crazy with all the valve train noise. MK
Dunno..If it is, you will know it. The engine should be clacking like crazy with all the valve train noise. MK
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From: Broken Arrow, OK
I'm gonna take a real long shot here. Pull out the distributor and check the oil pump drive shaft. Ford is notorious for using weak oil pump driveshafts. When the cam gear went the sudden stop of the cam could have bent the shaft or damaged the roll pin that retains the distributor gear. As a result you might have been running with a bent oil pump driveshaft. That would drive the distributor crazy and cause rough running. The same thing could have happened with the roll pin.
