power tilt and trim

[mcruea]

just put new o rings in the check vavles , pretty worn out rings , the motor stays up know ,works good going up and down , but the problem im having is in the water , while im moving the trim wont raise the motor and if i stop it will raise , but when i put it in gear it slaps the motor down fast , but when i put it in reverse the motor stays still,im wondering if the cylinder needs new o rings , and how hard is it and the best way to take it a part ,plus does any body know where i can get pc of aluminum that goes around the boat with the rubber center , i think it acts like a bumper
thanks for the help
mcruea

 

[roscoe]

Re: power tilt and trim

Need more info, like make model and year of motor.

 

[RRitt]

Re: power tilt and trim

Let us assume that the motor is spinning properly.
Then it's probably in the pump. Some small chance that it is in the tilt ram. Even smaller chance that it is in trim cylinder. (system should still bleed down if either of these was bad).

Personally, i think you should go to ebay and look for my pump/motor rebuild. It's cheap and it works properly. I get pumps with stripped threads, with thick layers of goo, encrusted with rust, with holes drilled in the release plugs, you name it - i get it. The number one cause of pumps being ruined beyond repair is boat owners who take them apart.

 

[mcruea]

Re: power tilt and trim

its a 1986 hydro sport with a 125hp and there is no bleed down , it will stay up all day untill you put it under pressure

 

[RRitt]

Re: power tilt and trim

its a 1986 hydro sport with a 125hp and there is no bleed down , it will stay up all day untill you put it under pressure

no bleed down is one of the primary reasons I think it is pump. it could be bypass valve in tilt tube, but that is unlikely. The rest of slave hydraulics is just classic piston and tube stuff like the brakes on your car. No bleed down indicates good piston rings.

 

[mcruea]

Re: power tilt and trim

so is the pump very hard to rebuild

 

[RRitt]

Re: power tilt and trim

It is not so much that it is hard to rebuild. It is more a case of being very easy to mess up. You should try redoing the release valves one more time. Make sure there is no debris and use viton o-rings. Lubricate with vaseline or thin coat of trailer grease before assembling.

 

[mcruea]

Re: power tilt and trim

sorry rritt cant take the advice about buying a new one , hrs has been cut to 32 a wk at work , so i went ahead and took it apart my self , im pretty good with hands on stuff. but just want to make sure theres only 2 springs and 1 large bb and 3 small bbs. i only see one way it goes together, so i hope i do it right, i under stand if you dont tell me how it goes , if you do nobody would buy the rebuild ones , but are the parts right thanks for the help
mcruea
plus it was pretty dirty grey looking stuff i think that from water mixing with the oil

 

[RRitt]

Re: power tilt and trim

it varies from model to model.
some have two springs and some have three.
some have no ball bearings, some have five, and others have anything between.

tips -
there is a hollow space below valve seat so you can not reface the valve seat, resuface the lower casting, or bead blast anything without removing the valve seat(s). use vaseline when reassembling. assemble unit upside down. most important - don't force anything. aluminum is soft. if you force it then you'll probably break it.

settings:
Spring compression varies from model to model based upon what type of valves are installed. You can calculate it by multiplying surface area of opening in valve face by 750PSI. For example - if your valve seat has a 1/16" opening then compress the srping to 2.3Lbs.
If you do not have a spring gauge then just start with four shims and use a pressure gauge to check output after assembly. Pump should deliver 700-800 PSI thrust and 350-600PSI hold. Too much pressure shortens lifespan of system. Too little pressure doesn't lift engine. Check pressure, reshim, recheck. It may take three or four (or five or six) tries to get it right.

or (from the school of duct tape repairs) -
Hook it up to engine using temporary tubing and the tilt ram. Hang some extra weight on prop. I dunno how much, maybe 20 lbs or so. run system up/down a few times to get out air. run it all the way up. if it doesn't lift then add shims to forward valve. If it lifts but has pressure lock on full extension then reduce front shims. keep shimming and reassembling until you can lift without getting pressure lock.

 

[mcruea]

Re: power tilt and trim

ok i got it back together with out any shims , i put it back together the way it came apart, anyway it will go all the up , but it only comes down sometimes and some times it stops like it hit a brick wall , may i put it together wrong i dont think so or is there still some air in the lines or pump , and not really sure what your talking about shims where do they go if i need them , thank you for your help alot really do mean this

 

[RRitt]

Re: power tilt and trim

if you didn't have any shims then you probably had an adjustment screw. if the mood strikes you then you should put two small washers between top of spring and bottom of hex adjusting screw. Sometimes the pumps malfunction because the spring gets hung up on the threads.

same settings as before just turn the screw instead of adding shims. take care not to wallow out the resevoir holes. you're probably going to need to take it apart and put it back together a few more times before you get everything to work just right.

 

[mcruea]

Re: power tilt and trim

i hate to keep bugging you , but i dont see any adjusting screw the style i have is the snap ring that holds the plugs maybe that let you know what im working on , have you ever seen a plug blow apart when you take it out , well i took the snap ring out and hit the switch and the plug blew a apart , im lucky i found the spring and the needle plus alot of air came out , so i figure that was the problem, so i put new o rings on it and put it back together and tried it and it work so i gave it a test and push down on the motor to see if it move and it did it drop like a rock and seen something flew well it was a bolt . i notice that a bolt was broke on the little plunger(trim ??) already well a nother broke and the cylinder was crooked so i think i was loosing all of my power there because after that happen nothing would work , i took it apart and o rings were no good .so i have to rebuild that tomorrow , plus how do you take the cylinder apart with out messing up the holes i figure i got it out my well rebuild it to . ill have a hole new unit when im done im sorry to keep asking you for imformation to do stuff but when you never work on one what do you do , i can fix a car or combine any time i want , but i know what im doing when it comes to that . im not afaid to try to fix something so thanks alot , if you live close to me id probly pay for all the information you given me. again thanks alot
mcruea

 

[RRitt]

Re: power tilt and trim

if you have the pressure set wrong then it can blow the top off the manual release valve. it can also be caused by worn out metal or an extremely forceful blow to engine. the cap is a press fit. if it is not a snug fit then plug assy should be replaced. but replacing plug probably isn't an option for you. i dunno what to suggest if that is case. maybe a dab of red locktite?

at any rate, you need to finish fixing the pump before you start taking cylinders apart. just plug up the trim ports and use the tilt cylinder to help you finish pump. Once your pump is a "known good" then move onto rebuilding the slaves. If you don't start with "known goods" and build your way up then you might end up chasing your tail.

if the trim cover bolts are broken off in holes then you may have to machine them out and go to 5/16". which is fine but you'll also need to cut the cover through holes and seats. don't even mess with regular drill bits. they won't get a clean cut on the SS and they are likely to wander off center and make your problem go from bad to worse. use cobalt. you can buy resharpened aviation bits off ebay for $20 per 100.

 

[mcruea]

Re: power tilt and trim

the bolts are out enough to get to so im lucky , i still dont see a pressure set screw so i look again in the morning , thanks for all the help
ill let you know if iget every thing in working order
mcruea
how do you remove the cover on the cylinder with out screwing up the holes , do i need to make up a tool to do this and sre they right hand threads
thanks again

 

[RRitt]

Re: power tilt and trim

it is a 3/16" spanner wrench. the best one is an armstrong adjustable type. You can get them from any industrial tool house for about $25. Normal threads.
if it is fused then depress tilt piston so that you don't melt orings on piston and heat top cover until rubber bubbles. take off top while hot. If you do this then you will need to find a place that will sell you a urethane top seal. You may need to buy a bag of 100 and they cost from $1.50 to $5 each. So - - if top is fused, maybe it is better to leave it alone.