Engine Overhaul Kama 554

[doxford jim]

Hi Rob,

I would still be inclined to look at the ajusting arrangement for the oil pressure - it isn't going to cost you much at all. First I would try adjusting the pressure up using the adjusting screw and locknut. When the engine is warm and the oil pressure down to whatever, then try increasing the pressure a bit and see what happens. Usually screwing in tightens the spring which in turn increases the pressure.

If that doesn't work or do the job, take the spring out and then check the valve itself - it could have a damaged seat on the valve or, the seat that the valve sits on could be damaged or might just need cleaning up with an end reamer or similar tool. Last but not least, the spring could be weakening or giving false reading when the oil is warm - so replace it with a new one. Another real cheap check is to put a washer behind the spring and replace and see what happens without playing with adjustments.

I would expect the pressure adjustment may have changed - for whatever reason. As long as you can get say 40psi when the oil is hot, you should be fine.
Often adjustment will do that - and it is free. Better still adjust up and down so you can really see what is happening, it will help.

On the old JD450 I rebuilt - before the rebuild, the oild would drop to about 25 psi after everything was hot. After the rebuild and replacing both the spring and valve, the oil pressure stays at around 45 psi when hot - which is more like it is supposed to do.

Don't go worrying about the rebuild if it ain't necessary - check the other variables first. My take is you just need to adjust the pressure up maybe 20 ppsi using spring and ajusting screw. Run until hoot and then see waht pressure you have. Cold oil can be very deceiving and throws a person out - it is the hot oil pressure you need to adjust.

HTH

Jim

 

[doxford jim]

Hi Rob,

I would still be inclined to look at the ajusting arrangement for the oil pressure - it isn't going to cost you much at all. First I would try adjusting the pressure up using the adjusting screw and locknut. When the engine is warm and the oil pressure down to whatever, then try increasing the pressure a bit and see what happens. Usually screwing in tightens the spring which in turn increases the pressure.

If that doesn't work or do the job, take the spring out and then check the valve itself - it could have a damaged seat on the valve or, the seat that the valve sits on could be damaged or might just need cleaning up with an end reamer or similar tool. Last but not least, the spring could be weakening or giving false reading when the oil is warm - so replace it with a new one. Another real cheap check is to put a washer behind the spring and replace and see what happens without playing with adjustments.

I would expect the pressure adjustment may have changed - for whatever reason. As long as you can get say 40psi when the oil is hot, you should be fine.
Often adjustment will do that - and it is free. Better still adjust up and down so you can really see what is happening, it will help.

On the old JD450 I rebuilt - before the rebuild, the oild would drop to about 25 psi after everything was hot. After the rebuild and replacing both the spring and valve, the oil pressure stays at around 45 psi when hot - which is more like it is supposed to do.

Don't go worrying about the rebuild if it ain't necessary - check the other variables first. My take is you just need to adjust the pressure up maybe 20 ppsi using spring and ajusting screw. Run until hoot and then see waht pressure you have. Cold oil can be very deceiving and throws a person out - it is the hot oil pressure you need to adjust.

HTH

Jim

Rob,

I forgot to mention that there should be an oil pressure adjuster on the engine oil filter housing - at least that is where my one is, yours might be different. But you do need to be sure that you are getting proper pressure when the engine oil is good and hot. You will also need to determine an engine speed that you would use as a referens - 1800 rpm, 2300rpm etc. That will give validity to what you are doing and ensure the correct pressure for a given RPM.

Others have said 10 psi / 1000 rpm. So given those figures 25psi is acceptable at 2300rpm. I would be inclined to adjust the oil to about 40 psi for 2300 rpm hot. Others my disagree, but if they do they will usually give another figure that they consider right.

HTH

Jim

 

[greg_g]

I think the actual engine specs (FeiDong manual, pages 7-8) should take precedence.

• engine idle (hot) - minimum 49 KPa (7.1 psi)
• 2500 rpm (cold) - not more than 450 KPa (65 psi)
• 2500 rpm (hot) - 250 KPa (36 psi)
• Oil pressure adjustment procedure (in semi-coherent Chinglish) is on page 21.

They define "hot" as oil not to exceed 100C, and/or coolant not to exceed 95C (ideally ~80C)

//greg//

 

[ToadHill]

From my experience engine oil pressure is a function of design. When I raced sports cars, my Alfa Romeo never ran oil pressure above 45 lbs, even at over 9000 rpm. The sump held 12 quarts and the pump sent a high volume of oil into the system. I had a friend with a Mini that had a 4 quart sump and if his oil pressure fell below 90 lbs he would spin bearings.

I guess I don't understand how a number like 10 lbs per 1000rpm can work for all applications.

 

[greg_g]

I guess I don't understand how a number like 10 lbs per 1000rpm can work for all applications.

I agree, which is why I cited the FD395/495 engine manual.

Case in point: oil pressure in a used 3/4 ton Chevy I bought several years ago had me concerned, until I looked up the numbers for that particular 350. Believe it or not, that particular 350 is spec'd to only run
6 psi @ 1000 rpm,
16 psi @ 2000, and
24 psi @ 4000

//greg//

 

[IH3444]

10/1000 is just a general rule of thumb. My 911 engine at idle has about 15psi with M1. If you just blip the throttle it jumps right up to 60psi.

I think your journal is still OK Rob. The plastic gauge material I believe confirms this from your photos.

I would first check if there is any adjustment for the oil pressure relief, either at the filter, or in the sump just off the pump, as others have recomended.

I shimmed mine in the International backhoe BD154 engine with a 0.100" shim, and installed new oil pump gears. This is after finding by a lower end inspection the center connecting rod bearings were down to the copper after purchasing. The journals when miced were worn 0.0015". My oil pressure at 2000 rpm went from 30psi, to 45psi. At operating temperture, after before mentioned work was performed.

Did you mic the backlash in your pump gears? Mine were speced at 0.020" max clearance between teeth. Hence new gears installed.

I use Rotella std. Dino diesel 15w-40 oil in the old hoe.

There were no 0.001" oversize bearing available, so I installed a fresh new std set. And polished the journals while the crank was still in the engine like you did.

Then shimmed the oil pump relief by my engine machinist buddy's recomendation. He has much more experience than I.

I haven't had one moments trouble with the old hoe engine since, and that was 21 years ago. Like everything I've owned, I've run the ever living snott out of it. Not a peep of trouble, or knock.

My old connecting rod bearings were down to the copper, although no knocking wa heard.

Also I've found that Mobil fully synthetic engine oil holds 10psi more after complete warm up at above idle running rpms. This is by the gauges in the Porsche. Break in on regular dino oil, then switch to full syn M1.

 

[3RRL]

Good advice guys,
I will look into adjusting the oil pump then.
It is, after all, going to be easy to check ... a lot easier than tearing the motor all apart again. I have Wes here this weekend so I'll be spending time goofing off with him. Plus I'll have time to cool down a bit over this because I was so dang disappointed about not fixing everything. I'll report back later next week. If I have questions (more than likely) where the the adjustments on my Kama are, I will ask.
Thanks again,
Rob-

 

[3RRL]

I have an after market oil filter unit which takes a spin-on Baldwin filter.
It was a "bolt on" unit. any idea if I can adjust the oil pressure using that?
Here's a photo of it.
Rob-

 

[greg_g]

any idea if I can adjust the oil pressure using that?

No fact, just supposition. But given that American spin-on filters are almost universally presumed to have a built-in bypass valve, good chance those hex heads on the left side have something to do with oil pressure..

I was thinking recently of installing that same filter head on my KM454, but lost the link to the website that sells that device. Do you remember who makes and/or sells that thing?

//greg//

 

[doxford jim]

I have an after market oil filter unit which takes a spin-on Baldwin filter.
It was a "bolt on" unit. any idea if I can adjust the oil pressure using that?
Here's a photo of it.
Rob-

Hi Rob,

It sure looks lik the adjustment to me. The cap nut should be removed and that will expose a screw (aften slotted, but could be an allen screw) with a lock nut. Slacken the lock nut off and then turn the adjusting screw in say 1/2 turn. Lock in place and then run your engine and see what the pressure change is - keeping a good eye on the pressure just to be sure. Usually screw in increases pressure and screw out decreases pressure.

One other thing worth checking is to take out the regulating vale to check the condition of the spring and the valve seat and valve. If vale seat/valve is damaged, it will register a lower pressure as the valve does not close properly - ie leaks a bit - same if a bit of debris becomes lodged under valve.. If valve seat and valve are in good condition and the spring good, then probably all that is needed is an adjustment.

HTH

Jim