Oil Pump (?) Info

[neildeb2]

ave a 58 LRC w/ 4-71N's. On the rear inboard of each engine is a moderately large pump to quick a tachometer sender is attached. The pump is clearly connected by hoses to the Allsion MH30 xmsn's. I assume this is the xmsn oil pump. The Allison manual says refer to the engine manual for oil pump info. The DD service manual says refer to the xmsn mfr manual for info regarding the xmsn oil pump. The pump is dripping very clean and clear oil, so I conclude it must be the pimp for transmission oil. But I can't find anything on the pump so I can disassemble it and (hopefully) repair it. Anyone have suggestions on locating a manual for this pump? Anyone have experience fixing leaks in this pump? Thanks in advance.

 

[osprey]

https://www.heavydutykits.com/product/seal-kit-hydraulic-pump-allison-marine-gear/

 

[neildeb2]

Thanks. Have you had the same issue before?

 

[Captain Ralph]

Could you send in a picture to help I D the 1 in 4 pumps that have been in use since original?
Any numbers or notes cast / stamped on the pump?

 

[SKYCHENEY]

Hydreco pump. Acadian Marine will have the info you need.

 

[neildeb2]

It's a hydreco 1413A-SP1 hydraulic pump for the transmission (thx Skycheney for the lead). I'll try Acadian marine. My phone only takes HEIC pics, and the site won't allow attaching them. It appears to have only 2 gaskets...

 

[neildeb2]

Skycheney, I spoke with Acadian Marine. They were great and, as predicted, they had what I needed. Thank you again for the lead.

 

[zigzag930]

Neil,

Hi. Did you rebuild those transmission pumps? Was it just a gasket that was leaking?

For the 1st time today, I noticed that both pump have a slow drip. Looks like it's coming from the front (toward the bow) side of the pump.

What level job is this and any special tools?

Thanks,

J

 

[Scarlett]

Save some hassle and remove the pump and send it to Acadian and let them rebuild it. They were very reasonable, not a whole lot more than the cost of the rebuild kit. However with shipping cost out of site now that may not be S good an option.

 

[zigzag930]

Called Arcadian Marine and spoke to Brian. He's terrific and explained quite a lot about this pump, how to fix the leak quickly and how to adjust the pressures.

My pumps are running at 90 and 100psi. Brian told me that is way too low and that my transmissions are most likely slipping at those pressures. That would probably explain why I run at lower speeds that my chart shows for a given RPM.

Any other Detroit/Allison owners able to chime in with the pressures they see on their transmissions? I have 471N's

Thanks
J

 

[cww]

My port transmission slips at high throttle settings before it fully warms up and the port gauge reads slightly below 110 where the starboard gauge reads slightly over 110, that one never slips. Is this a thing, are they really that sensitive? And they're adjustable? How do I adjust it? I was just babying it because I thought I was going to have replace or rebuilt it. What's the procedure for turning the pressure up?

 

[zigzag930]

According to the tech I spoke with, they ARE that sensitive. He said at 100psi, that is about the minimum for forward gear to engage. Reverse is lower about 60psi.

They are adjustable. There is a large 1" long nut, with locking nut snugged against it on the side of the pump opposite the suction side (bottom in my case). Tech said to remove the 1" nut, then loosen the lock nut. Once that is done, you can insert a screwdriver in the bottom and turn clockwise to increase the pressure. He said that you should monitor the gauge while doing this. Pressure may increase first, then decrease, but then rise again. Do it slowly and keep watching until steady pressure at 1200RPM or so reads 135lbs.

I have not done this procedure yet, so I can't comment on how it work, but does sound pretty simple.

 

[SKYCHENEY]

You could also call Acadian Marine gear and talk to Brian Lemmon, Vice President. They are the experts on Allisons and very helpful.


337-837-3636

 

[zigzag930]

Yep, Brian is the man I spoke with. He was a tremendous help.