FYI Perkins again

[Brooksie]

I finally decided to hoist my Perkins HT6.354 out, remove the oil pans, check the bearings & oil system and get to the cause of two problems. 1) chronic low oil pressure
2) oil runs from the tank to the crankcase while not in use giving a false low reading on the dipstick.
I used threaded rod and cross beams to raise the engine high enough to remove the oil pan, clean the bilge under, remove the main & rod bearings, oil pumps, pickups, and associated piping.
I checked all the rod bearings and they looked like new. With Plastigage they showed .002 clearance. so not the problem.
I only checked the 5 central main bearings, same as above looked new and .003 clearance.
On close examination there was a little wear on the oil pump rotor and none on the end caps. But I replaced it anyway.
I made an adapter and checked the relief valve on compressed air. It opened at 55psi consistently so that wasn't the problem.
The seal between the 2 oil pans (this is a dry sump system) was hard as a rock but in good shape. This is the only way oil can get from the tank section to the block section. It was bunaN but I replaced it with Viton which should remain soft enough to take up the expansion between the 2 sections which must be letting the oil pass while shut down.
Finally, and I'll know when I get it back together and started, I think the oil pressure problem was caused by two 11/16 ID Orings on the oil pump outlet/relief valve inlet connecting tube. They were hard as a rock, cracked in several places and flattened ID & OD. One Oring seemed to have a small piece missing but I can't be positive of that. I have replaced them with Viton rings also.
B/4 I close it back up, I will use my air adapter mentioned above it blow air into the oil system to be sure that I don't have a bad cam bearing or the #1 or #7 main bearing isn't bad or some other crazy thing that I can't see.
Final report to follow

 

[DavidM]

Great report!


You did all of this as an amateur, right? How many professional mechanics would have done this stuff. I suspect nearly none. We are a throw it away, or change the part no matter the cause, society.


David

 

[Duvie]

Oil level

I thought I read in the Perkins manual that the oil level on the HT6.354 had to be checked immediately on shutdown to get an accurate reading. Maybe you don't have a problem?

 

[Brooksie]

I thought I read in the Perkins manual that the oil level on the HT6.354 had to be checked immediately on shutdown to get an accurate reading. Maybe you don't have a problem?

You are right, or check even while running at idle. So I could always check it but never b/4 startup. Also it seemed to take a long time to build oil pressure upon start maybe b/c the pickup is in the oil tank part of the pan and the oil had migrated into the block part. But mainly I undertook the project to look into why never more than 30lbs pressure falling to 10 at hot idle and finally, last month my oil pressure light blinked at me. I took this as an indicator to do something. The boat this engine is in (not the Willard) was designed around this horizontal engine and no other engine could replace it so it isn't just a matter of being frugal, nothing else would ever fit in it's place.

 

[kulas44]

The Cummins 6BT could be had in horizontal, and any of the inline DDs. I am not familiar with the dry sump system that you mentioned on your engine. I've had and worked on dry sump systems just not on a 6-354.

 

[hypersloth]

Is the remote tank connected to the pan or is it a separate stand alone tank? My stick looks like it enters side of dry sump pan. I own two other dry sump vehicles both with remote tanks and don't know why I've never thought where the perkins stores its oil. Sitting here early am fuzzy headed.

 

[R_p_ryan]

wow, big project! congratulations on taking on such a scale, and good idea to use threaded rods. Persistance is a great quality.

 

[Brooksie]

Is the remote tank connected to the pan or is it a separate stand alone tank? My stick looks like it enters side of dry sump pan. I own two other dry sump vehicles both with remote tanks and don't know why I've never thought where the perkins stores its oil. Sitting here early am fuzzy headed.

The tank is a 2nd segment of the oil pan and bolted to it with a 2nd oil pan gasket and 24 more bolts.

Mostly I mentioned this whole proceedure b/c the 2 Orings I think, at this point, that are responsible for the low oil pressure and slow rise of oil pressure on start are a part of every Perkins both 4 & 6 cylinder vertical and horizontal. So others with low oil pressure and priming problems may benifit from my experience.

 

[High Wire]

Any progress report?

 

[Brooksie]

Any progress report?

Thanks for asking. No not a final report but after checking almost all the bearings, installing new oil pump, cutting new gaskets, I am ready to go back together.
However I am hung up on 2 parts. The scavenge pump drive gear is quite worn and no longer available so I am investigating having one made. I am also still stuck on the seal, which I insist must be Viton, that goes between the oil pan & tank on the pump suction pipe. This is the only place where oil can seep from the tank to the crankcase when not running.
BTW, if anyone knows of a horizontal being parted out, I would appreciate hearing about it b/c having that gear made is going to be expensive compared to finding a good used one.

 

[Rossland]

The scavenge pump drive gear is quite worn and no longer available so I am investigating having one made. .

If this gear is also used on the vertical versions of this engine, contact a Massey-Ferguson tractor dealer. My experience with these engines in farm machinery is that virtually all parts are still available. BTW, I also had a problem with low and slowly declining oil pressure. I replaced the oil pressure gage and sender, and now the oil pressure is back up to factory specs (60 psi)

 

[Brooksie]

If this gear is also used on the vertical versions of this engine, contact a Massey-Ferguson tractor dealer. My experience with these engines in farm machinery is that virtually all parts are still available. BTW, I also had a problem with low and slowly declining oil pressure. I replaced the oil pressure gage and sender, and now the oil pressure is back up to factory specs (60 psi)

Rossland, Thanks for your reply. I already checked my OP gauge with a mechanical gauge and they both read the same. I did order my new oil supply pump from a Massy dealer but I don't see where this gear could be used on a vertical engine since they have no scavenge pump. I did look at the oil pump & balance shaft gears on other Perkins/Massy engines to see if I could find a similar gear that could be modified but they all seemed to have spur teeth and this one is helical cut. If you have a lead for me, I am "all ears"
Thanks

 

[Brooksie]

As promised, here is a final report on opening up my Perkins to investigate & correct low oil pressure and, since this is a horizontal model, oil "disappearing" from the tank section of the oil pan while moored. Naturally the "disappearing" oil, from tank to crankcase, would only be of interest to owners of horizontal engines. There are only 3 places where oil can get from one section to the other, The "window" way at the top of the tank and this would only happen if the tank were massively overfilled. The bolts that hold the strainer on, unlikely but I put Loctite on them in case. Finally the "donut" seal between the strainer and the tank which was hardened up but still good. This I replaced with Viton washers which should stay soft.



In addition to the worn scavenge pump gear which I had made. One of the impellers has 2 bushings in it with a space between them for oil, these were worn and one had slipped against the other blocking the oil hole to the shaft pin. No measureable damage was done but I am glad I discovered it and replaced the bushings with a single bushing. I grooved it for oil flow and added a second oil hole between impeller teeth. Also added a setscrew and Loctite retainer to the pin so it could not turn in the pump cover. Interestingly, ah the Brits, the impellers (gears) in this pump are longer than the pump housing so the choice if gasket material for the end covers is critical to setting up the clearance.



Finally to the low oil pressure issue. Although I replaced the oil pump for good measure, the old one had no wear to speak of. I was able to find a new, British made, one of the same brand as the original. So I did it. I pressure tested everything, relief valve, flanges, pickup tubes, just to be sure. So I must conclude that the two Orings between the oil pump and the relief valve were actually the fault b/c upon restart I had 50lbs oil pressure which I have never seen b/4. All 6.354 engines, horizontal and vertical has these Orings and they are not Viton so prone to hardening and cracking.



I might also mention that I did away with the "in tank" oil cooler and mounted a normal one (300psi) because the stock one was only 1/2 covered in oil inside the tank when the tank was full. A much better cooling arrangement from several standpoints so I expect that even after a hard run, I will now have good oil pressure.

 

[Knot Salted]

I finally decided to hoist my Perkins HT6.354 out, remove the oil pans, check the bearings & oil system and get to the cause of two problems. 1) chronic low oil pressure
2) oil runs from the tank to the crankcase while not in use giving a false low reading on the dipstick.
I used threaded rod and cross beams to raise the engine high enough to remove the oil pan, clean the bilge under, remove the main & rod bearings, oil pumps, pickups, and associated piping.
I checked all the rod bearings and they looked like new. With Plastigage they showed .002 clearance. so not the problem.
I only checked the 5 central main bearings, same as above looked new and .003 clearance.
On close examination there was a little wear on the oil pump rotor and none on the end caps. But I replaced it anyway.
I made an adapter and checked the relief valve on compressed air. It opened at 55psi consistently so that wasn't the problem.
The seal between the 2 oil pans (this is a dry sump system) was hard as a rock but in good shape. This is the only way oil can get from the tank section to the block section. It was bunaN but I replaced it with Viton which should remain soft enough to take up the expansion between the 2 sections which must be letting the oil pass while shut down.
Finally, and I'll know when I get it back together and started, I think the oil pressure problem was caused by two 11/16 ID Orings on the oil pump outlet/relief valve inlet connecting tube. They were hard as a rock, cracked in several places and flattened ID & OD. One Oring seemed to have a small piece missing but I can't be positive of that. I have replaced them with Viton rings also.
B/4 I close it back up, I will use my air adapter mentioned above it blow air into the oil system to be sure that I don't have a bad cam bearing or the #1 or #7 main bearing isn't bad or some other crazy thing that I can't see.
Final report to follow

Incredibly helpful seven years later…keeping this in my notes to check file![emoji106]