Allison advice, no forward!!Please help.

Sorry everyone for being a pain the butt, but I have one last question and I'll leave everyone alone
I'm having trouble with the port motor not shifting into forward. I've got reverse all day but no forward consistently. I had it working for about 6 minutes. It would take anywhere from 20 to 10 seconds to shift into gear. When I stopped trying the forward gear was no where to be had. I've changed the filter and I looked at the strainer. I have a psi gauge on the shift lever gizmo and it hold anywhere from 25 to 75 psi. I haven't run the other motor and compared pressures to see whats happening but does anyone have advice besides call a mechanic. I talked to the local parts house and they have a forward rebuild kit. Do I have to take the trans loose from the engine? I want to do as much as I can myself so I can learn and save money. Thanks guys Paul

This might seem a silly question...but is your linkage properly set to shift the transmission into forward?

These guys offer a fair bit of information on their site. I don't know if any of it is of use to you.
FAQ - Acadian Marine Transmission

They have been recommended many times by folk on Boatdiesel. I have no experience with them other than that.

Which model do you have?

Any advice???? I can offer about this gear is worthless. Just hope that maybe this name is of some use.

I do suspect though that you will have to remove the gear.

JAT that is not a silly question at all, but I don't have any linkage because it was burned up. The lever is set in the proper position though. C lectric thanks for the site, I am going there now. Paul

Swampu, can you identify the make of marine gear? A common setup should possibly have 3 test ports to check pressures. The equipment I work on operates on the same principal. Pump pressure might run 125-160 psi. F and R test pressures might run 110-145 psi. There will be a forward and a reverse clutch pack and the pressure is ported to these and it pushes a piston with in the pack that pushes the discs together to "engage" the pack. Low pressure to either pack would not apply enough force to push the discs together. Or the discs could be worn to the point that the piston can't move enough to push the discs together. I am told Zimmer Gears (Earl Zimmer) in Baton Rouge is an authority on Borg Warner Velvet Drives, 225-927-6125

forklift, I think my pressure is to low. I never got over 50-75 psi. I am waiting on a thermostat gasket and then I'll run the other one and see what it's pressure is. After I run the other engine and if it is in fact bad clutches or pump I'll call Mr. Zimmer. Thanks Paul

K. I just read the title again and see it is an Allison. Maybe Earl can help. Keep us posted!

So being Alllison, not Borg Warner, puts Mr. Zimmer out of the Frame? BruceK

BruceK said:

So being Alllison, not Borg Warner, puts Mr. Zimmer out of the Frame? BruceK

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Probably so. But it sure would be helpful to find someone experienced with the product willi g to share information. Clectric mentioned Acadian. They look like a great choice.

I just checked out their site. Under general info they show Forward pressure to be 130 psi @ 1800 RPM. Reverse is 110 @ 1500. When you check you pressures again you would need to speed the engine up quite a bit. This could raise your pressure considerably. Not to mention. Kicking up a fuss with the prop

Swampu
Possible causes from manual,
1.Low oil pressure
2.Worn forward clutch facings
3.Improper dump valve operation
4.Damaged forward clutch pack
5.Damaged reduction gear
I have the manual, i can email to you,send your email address and will forward it to you.
Bluetide

I am thinking it's the oil pump. I cleaned the strainer. There was nothing in the strainer but when I put it back together the pump wouldn't pick up the prime. No prime=no pressure. When I cranked it up I had both forward and reverse. Back and forth for probably 5 minutes until I lost pressure gradually. I cleaned the strainer and it never picked up pressure. It is a MH 301 model.

Paul, pumps build volume. Not pressure. Is there an external line from the pump to the control valve that you could check for oil flow? Also, anything to do with the strainer, like orings on oech end that might have gotten cut?

Forkliftt said:

Paul, pumps build volume. Not pressure. Is there an external line from the pump to the control valve that you could check for oil flow? Also, anything to do with the strainer, like orings on oech end that might have gotten cut?

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There is an external line from the filter to the control valve which I was going to take off monday and see if i'm getting flow. There are gaskets on the strainer which are gone. There is a lot of sealant gooped where the gasket was. I think I amgoing to check all the lines for good seal and if all else fails take the control valve off which will probably cause springs to go everywhere. All very good suggestions and I believe I will follow them all.

http://www.acadianmarinetransmission.com/uploads/8V71TRANS.pdf

Paul,as I read through this service manual, on page 6 there is a description about how forward gear operates. There is a dump valve that must move to allow oil into the shift piston. the dump valve does not come into play when using reverse. That valve might be stuck causing your very slow shift or no shift.
in any case, my company is an Allison Authorized Overhaul Dealer. I will run your problem by one of our tech guys tomorrow and see what they say.
johnma
390 Mainship

That's why I love this site!!

johnma, you da man. I was going to start with the suction line. Replacing the seal. Than check the line coming into the valve body to see if I am getting pressure. Gauge says no pressure. I might have a clog at the oil cooler. I will take it off last and check to see if it is clogged. Somewhere i'm loosing pressure. Thanks for the help. Paul

Paul
I spoke with our tech guy this morning. He has a lot of experience with these. He said your pressure is low, but without looking it up he did not remember what normal should be. he wants you to check pressure in both forward and reverse at about 1500 rpm's. If reverse pressure is ok (100 psi plus) then it is either your seal on the forward shift piston or as I suggested yesterday, your dump valve. In either case, the transmission and flywheel have to come out. if pressure is low in both directions, it's your pump, suction line, strainer (sucking air maybe) or cooler (it is in line between the pump and control valve). All of those can be fixed without removing the transmission. Our tech guy is Dave Dusi, and you can reach him between 8:00 and 4:30 eastern time at 856-910-7979 company name is TRC in Pennsauken NJ (division of Transaxle) if you call him, reference me, John Malley

John

John, Thanks. I am going down there in the am to put the newer strainer and gasket on the suction side. I think that will fix the problem but I will post my findings tomorrow. Thanks again for your help. Paul

Well, an update. The transmission is out of the boat and setting on the dock waiting for the local dealer to open up on monday. The parts man was kind enough to say he would take a look at it and that way sell me only what I need. I will most likely have them install the new seals and rubber parts that are bad. I don't know what the shop rate is but I would imagine that it can't be more than a 1/2 day job, hopefully under 400 for parts and labor. We'll see.

Swampu,
We occasionally rebuild a customer's transmission instead of installing a reman part. When we do this, the labor cost is fixed. In our case with a forklift, there would be a rebuild kit including all of the seals, discs and bearings. A reman convertor would also installed. Any additional "hard parts" necessary would be approved, the replaced. Having said all this, the one constant on price is the labor. The tear down, rebuild would be the same since we wouldn't disassemble it part of the way till we saw a problem and stop. There would be too much risk that other worn seals/ hard parts would fail soon afterward. So a labor price, even if only replacing the seals, should be predictable. If you are thinking a half day labor, at say $90, then your labor cost would be around $360. This seems very low to me, so I would consider getting a labor estimate before you begin. Heck, R&R is the hardest part. And you are handling that. Also be sure to clean or replace any external cooler hoses and cooler to remove any contaminates.

Forkliftt, thanks for the advice on replacing the hoses and clean the cooler. I drained all the oil out of the sump when I pulled it out and it was clean as a whistle. I'll find out monday morning the "bad" news. It will be nice though to get it done and get her going. This is the last piece of the puzzle besides an overheat problem with the starboard genset. Might be cruising before hurricane season yet!!!!!

I bet you will! We're going to be moving over to the new Gulfport Marina in the next 1-2 weeks. Might get to see you around there.

Paul
did you pull the flywheel as well as the transmission?
John

Not yet, I'll be pulling that tomorrow morning. Looks like about 8 or 10 bolts and it should slide out I hope.

new Gulfport Marina

Great spot , the lifestyle of Key West , small village , laid back and friendly , many great resturants and library.

But close to St Pete or Tamps to spend boat bucks .

FF

FF said:

new Gulfport Marina
library.
FF

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The library is gone the way of the hurricane. Got a new park and everything else is new now.

"The library is gone the way of the hurricane."

Not any more , it might have blown away at sometime , but a fine new building is within walking distance of the harbor. At least it was there in April. Free Wi Fi.

FF

Wow, I'll have to check it out, get it? Last time I was in gulfport harbor I was diving boats for a living, scrubbing bottoms and changing zincs. The harbor master died not to long ago. I forgot his name but if you were there and any point in the last 30 something years you met him. Maybe the old building is what is gone. There was a lot of debate on what to do with it.

Bluetide said:

Swampu
Possible causes from manual,
1.Low oil pressure
2.Worn forward clutch facings
3.Improper dump valve operation
4.Damaged forward clutch pack
5.Damaged reduction gear
I have the manual, i can email to you,send your email address and will forward it to you.
Bluetide

Click to expand...

Can you send the manual to karlpaterson77@gmail.com