410 Stoker help!!!! LOW OIL PRESSURE!!

[Mooch42]

I have a fresh 410 stroker. Bottom end is a eagle forged kit. Milodon 8qt pan milling HV oil pump. When the engine starts it has 60psi of oil pressure at idle, once it reaches running temp drops to 10psi at idle (1000rmp). Touch the gas and pressure jumps up to 40-50 psi. This motor doesn't have 3hrs of run time. No ticks or knocks no metal in the filter. I have already checked oil galley plug in the distributor hole and the one in the oil sending unit hole they are both there.. Has anyone come across this..

 

[RustyRatRod]

Some have seen leakage from the two holes behind the camshaft thrust plate, when not plugged off with freeze plugs. Were freeze plugs used there? Also, what filter are you using? Sounds like you are on the right track and have eliminated the first to biggest suspects.

 

[rumblefish360]

New oil pump?

 

[Mooch42]

New oil pump?

Yes oil pump is brand new also

 

[Mooch42]

Some have seen leakage from the two holes behind the camshaft thrust plate, when not plugged off with freeze plugs. Were freeze plugs used there? Also, what filter are you using? Sounds like you are on the right track and have eliminated the first to biggest suspects.

I am using a wix filter. I didn't assemble the short block so I'm guessing that's my next place to check

 

[RustyRatRod]

I am using a wix filter. I didn't assemble the short block so I'm guessing that's my next place to check

I cannot think of another place right this minute.......I think that's it though. OR if the lifters are exposing the oil bands, that's another thing to check......unfortunately both those things do require some tear down. It sounds like you did right by the filter, at any rate. Good luck man. I hope you find something stupid easy.

Of course, I guess "you know" to verify the pressure with a "known good" gauge.

 

[Jadaharabi]

This is probably a silly question but is the plug-in Place underneath the oil filter adapter plate?



Is it a reliable oil pressure gauge?

 

[Mooch42]

I cannot think of another place right this minute.......I think that's it though. OR if the lifters are exposing the oil bands, that's another thing to check......unfortunately both those things do require some tear down. It sounds like you did right by the filter, at any rate. Good luck man. I hope you find something stupid easy.

Of course, I guess "you know" to verify the pressure with a "known good" gauge.

I have eliminated the guage I checked it with 2 other old guages and bled the line clear of air.

 

[RustyRatRod]

I have eliminated the guage I checked it with 2 other old guages and bled the line clear of air.

Well that's one more thing down. You're on the right track man. You'll find it!

 

[Mooch42]

Well that's one more thing down. You're on the right track man. You'll find it!

Ugh I hope so its giving me fits..lol

 

[Jadaharabi]

You could pull a valve cover and shine a light down inside to the lifters with the engine running and see if oil is gushing out the top of the lifter bore couldn't you?

 

[Mooch42]

You could pull a valve cover and shine a light down inside to the lifters with the engine running and see if oil is gushing out the top of the lifter bore couldn't you?

I think I am gonna pull the intake tomorrow and run the oil pump with a drill to see if I see anything like that

 

[RustyRatRod]

Yup yup. There's an idea!

 

[Jadaharabi]

Welcome to FABO.

 

[Jadaharabi]

You did use the milodon pick up for that pan didn't you?

La or magnum block?
flat tappet or roller cam?

 

[dusted]

Make sure the oil isn’t fuel diluted. I had the same problem on the 390 stroker and that was my issue. Carb would drip out of the secondary boosters when engine was off. Exact same pressure as described.

 

[flyfish]

What oil are you using? The reason I ask is I had the same thing happen on a previous motor. All I did was change from 10-30 to 15-40 oil and a different filter type...problem solved (however, I think you have a good filter, so maybe just a heavier oil).

 

[Mooch42]

You did use the milodon pick up for that pan didn't you?

La or magnum block?
flat tappet or roller cam?

The shop that put my short block together also installed the oil pan so I'm hoping they did. Its a LA block flat tappet cam

 

[Mooch42]

Make sure the oil isn’t fuel diluted. I had the same problem on the 390 stroker and that was my issue. Carb would drip out of the secondary boosters when engine was off. Exact same pressure as described.

I actually do have a problem with my fuel pressure being to high right now I just ordered a fuel regulator

 

[Mooch42]

What oil are you using? The reason I ask is I had the same thing happen on a previous motor. All I did was change from 10-30 to 15-40 oil and a different filter type...problem solved (however, I think you have a good filter, so maybe just a heavier oil).

I'm running a Kenndal 20/50 a good race oil

 

[j par]

I'm running a Kenndal 20/50 a good race oil

well that sounds like an easy one to check if you just have to change the oil and check the pressure again and see if your oil is not saturated? Just a thought. I know that's not cheap but easy

 

[nm9stheham]

• Did they put a new intermediate shaft at the distributor/pump gear to drive the oil pump?
• Was any info provided on how large they set the main and rod bearing clearances?
• PN's on main, rod and cam bearings?
• What are the idle RPM's and the actual RPM at which the oils pressure gets up to 40-50 psi when revved?

 

[stixx]

When the oil was diluted with fuel, shouldn't it give an indication on the dip stick?
And the oil should smell of gas, like badly? (just before you drain all your good oil)

 

[j par]

Just out of curiosity what are the cam specs? The last cam I had wouldn't hold an idol for over 10 or 15 seconds. is it a 4 Speed car or an automatic with a stall and how high is the stall converter? Some Motors don't like the idle at 800.

 

[nm9stheham]

Make sure the oil isn’t fuel diluted. I had the same problem on the 390 stroker and that was my issue. Carb would drip out of the secondary boosters when engine was off. Exact same pressure as described.

I would think you ought to be able to smell gas in the oil in that case.