Trim Problems. Help!!

[mochosla]

Hi all, I have a 1983 Regal with a 5.7 320 HP and a OMC 800 stringer outdrive. The motor has the twin piston trim but it does not work anymore. It has an oil leak so now when I gas the boat the motor goes up and down (it has trim play I guess?) by it self as the pistons are empty.

Question, can the hydraulic pistons be fixed? Can I buy them new? Can I cancel them out? I know the pump works but I don't want to add more oil to it as it ends up leaking it all out into my engine compartment.

Thanks.

 

[Bondo]

Re: Trim Problems. Help!!

5.7 320 HP and a OMC 800 stringer outdrive.

350s were 260hp or so in 1983,......
And,.....
Stringer drives used a Gear to lift the Drive.......... No Hydraulics....
So,.......
We'll be needing Alot More Info about your driveline to figure out Exactly What you've got................

 

[wire2]

Re: Trim Problems. Help!!

'83 and '84 stringers used hydraulic cylinders at the side motor mount positions. The driver's side also has the trim gauge sender.
Older OMC's used the gear/thrust bearing trim at the front of the engine, not sure what year it changed.
It now has air in the cylinders, which will compress and not hold its position. The only way to fix it is to first repair the leak, then fill it with oil again.

 

[aerwin]

Re: Trim Problems. Help!!

you have the select trim unit on your boat, OMC's answer to trim the outdrive. it is basiclly the motor mounts that have hydraulics in them and there is an electric pump elswere on the engine, usually on the side in the back. either you can repair the unit or find the regular motor mounts and pull the select trim out. then to help the boat, put on a pair of smart tabs. and your boat will be just as good. then you don't have to worry about leaking oil and that whole bad system. my 79' doesn't have selectrim. it just has the regular mounts. smart tabs made it a new boat

 

[mochosla]

Re: Trim Problems. Help!!

Hi Aerwin,

that's exactly what I have. I have 2 more questions:

1) When you say smart tab, are you talking about trim tabs? I already have those.

2) where can I buy the regular motor mounts?

Thank you.

 

[aerwin]

Re: Trim Problems. Help!!

if you already have trim tabs, thats cool. I like the "smart tab" brand because I don't have to trim the boat all the time. the smart tabs use a gas shock, like on a car hatch-back, to control to tab plate. the motor mounts should be very common, try e-bay or any boat parts place that has old surplus parts, sterndrive.com has alot of parts or even here at i-boats might have those. who knows mounts from mercury and v.p. might even work, its just a g.m. block with standard mounting holes.

 

[QC]

Re: Trim Problems. Help!!

The confusion on Stringer trim is that 400s (4cyl) uses a motor driven jack screw, the 800s (V6s and V8s) used hydraulic front mounts . . . Both of them use a motor driven gear for tilt.

 

[wire2]

Re: Trim Problems. Help!!

Thanks for the clarification, QC. I was under the impression that the vintage called up either a front jack screw or side hydraulic mounts. I stand corrected.

 

[mochosla]

Re: Trim Problems. Help!!

Thank you very much for your help. I spoke to a mechanic and he said that I HAVE to fix the hydrulic system. Honestly, I think he just wants to do the job. I will replace them with the regular supports.

Thank you again.

 

[Manipulator]

Re: Trim Problems. Help!!

mochosla, where is the leak at? Is there a loose hydraulic hose? Is there fluid on the stringers around the mounts? I have rebuilt these and it's not too hard. Low fluid will definitely cause the drive to raise and lower on its own. You can still order the seals. I saw a guy on eBay that made up seal kits and was selling them. Basically you run the trim all the way down (engine goes all the way up), then you take a 2X4 (I used 2) and you place it across the stringers and under the engine damper to hold the motor, then you run the trim up (engine down) and rest the motor on the 2x4, then you undo the hydraulic lines (mark them) and then undo the bolts to the motor and the then the lags. Taking the rams apart you remove the large nut at the bottom (piston shaft) and you will need an impact wrench for this. If you do not have one just run it up to the local auto parts store and they will loosen it, that is what I did. Then you can remove the mount from the piston shaft. Now remove the four small bolts on the body of the ram and then the whole thing comes apart. The piston pulls right out, install the new seals and reassemble. On the right you will need to unhook the trim sender and wire (two screws, no big deal).

As far as the jack screw system, I have seen it on 4 cyl, 6 cyl and 8 cyl. I know V8 Fords had it. I have never seen a jack screw on a GM, just Fords. I have seen older different looking select-trim on older Ford V8.

May want to take a look at this....
http://cgi.ebay.com/ebaymotors/OMC-...019QQitemZ290144778622QQrdZ1QQsspagenameZWDVW

 

[mochosla]

Re: Trim Problems. Help!!

This is great advice. I will try to take them apart this weekend. Do you by any chance have the contact info for the guy who sells the seals?

Thank you very much!!

 

[Manipulator]

Re: Trim Problems. Help!!

I don't know who that guy was. I no longer see him on eBay selling them. What I did was get mine through Doug Russell. com. You will need #10, #9, #8, #7, and #4 to do a complete rebuild. The place is a total rip off but it was the only place I could find that had the seals. I think I paid around $126 for all the seals/parts.

http://www.dougrussell.com/partscat...,3389,3390,3391,3392,3393,3394,3395,3396,3397

 

[mochosla]

Re: Trim Problems. Help!!

Thank you very much!! I bought my parts from the local shop (prices were a bit cheaper $120 for the part for both rams). Installed them on both rams and it worked like a charm.

Thank you all for your help.

 

[whywhyzed]

Re: Trim Problems. Help!!

That was me with the kits on eBay - I gave up - eBay customers are too demanding. Not worth my effort. Saving people 50% and getting them better quality parts somehow isn't worth a crap in that ebay-environment. Left me baffled. I faxed out a sheet to local marinas - now we're talking - people that know a good deal when they see it.

 

[mochosla]

Re: Trim Problems. Help!!

So, why did you remove the system from your boat? Do you have any other parts?

 

[bergerandfries]

Re: Trim Problems. Help!!

Ok, I now have this problem. I'll take pics as I'm doing it and post. WhyWhyZed, I'm gonna PM you to see if we can't work out a private sale, if you still have a source for the seals!