Adding Power Trim

[mercurymang]

Re: Adding Power Trim

Sure enough. I went out and measured. One cylinder is 1" and the other is 3/4".

 

[Yesterday]

Re: Adding Power Trim

I had suspected that from get-go. Look at the up-side though, you can use one of either size to get your pair. the ones on ebay are obscenely priced, because you can find other full motors with, for the price of one or two rams. That's how I ended up with 2 spares, but one needs rebuilt. In fact I got two full engines (both power heads shot :grumpy for $350.00.

Kijiji is where I'd be hunting. Trivia: I just learned recently ironically, that it's owned by Ebay.

<Added Note>:
Was reading the PT&T service manual tonight looking for that scan for you. These PT&T systems use low volume high pressure setups. Pump output tests are around 1900 PSI. Do you'll recall in my thread, the hydraulics guys I spoke to about the hoses saying they needed proper fittings, and couldn't repair them using crimp ons with the originals because there wouldn't be enough to hold them in place?

I'm guessing that would be why they said they wouldn't do it.. or IF they did, they would not guaranty them. Keep that in mind should you opt to go that route.

 

[mercurymang]

Re: Adding Power Trim

Ok, do you know if the hoses with the smaller fitting is low or high side?

 

[mercurymang]

Re: Adding Power Trim

I had an interesting conversation with a Mercury shop owner/tech this morning. The guy I spoke to is running a Mercury sales/service store that his dad opened in the 50's here is Fort Worth. His father has passed on and it is now his store. He said the early cylinders were the 1" and that Mercury decided they did not need one that beefy so they scaled it back to 3/4". In addition, he said that you can run them mixed like that without any problem. :noidea:

 

[Yesterday]

Re: Adding Power Trim

I had an interesting conversation with a Mercury shop owner/tech this morning. The guy I spoke to is running a Mercury sales/service store that his dad opened in the 50's here is Fort Worth. His father has passed on and it is now his store. He said the early cylinders were the 1" and that Mercury decided they did not need one that beefy so they scaled it back to 3/4". In addition, he said that you can run them mixed like that without any problem. :noidea:

So that means the valving where fluids leave the pump, must be split en route to the cylinders and they basically take what they need. well sir, THAT's a bonus!!!! I could also see the larger units being overkill! Not a bad thing, just costs more. Well then you're set?!

 

[mercurymang]

Re: Adding Power Trim

So that means the valving where fluids leave the pump, must be split en route to the symonders and they basically take what they need. well sir, THAT's a bonus!!!! I could also see the larger units being overkill! Not a bad thing, just costs more. Well then you're set?!

Ya, hopefully he was not blowing smoke. Turns out that the 850 i bought actually came from his shop originally as it had his old logo on it. At any rate, i'll try to hook it all up this evening and see if it works. I'll let you know how it turns out.

 

[Yesterday]

Re: Adding Power Trim

Any chance of salvaging the 850??

 

[Moody Blue]

Re: Adding Power Trim

In addition, he said that you can run them mixed like that without any problem. :noidea:

Not to dispute the tech but, that just doesn't sound right. The pump is outputting the same volume of fluid to each cylinder. The larger cylinder will take longer to "fill" as the ram is extended and equalize the pressure of the smaller cylinder will it not? If you take that example to the extreme, say a 1" and a 10" diameter cylinder you can see what I'm getting at. Also the pressure exerted by each cylinder will be different because the piston surface areas are different. I don't really know how the pump operates but it doesn't sound logical to me to be able to use two different sized cylinders. Hope for your sake that I`m wrong. Good luck.

 

[Yesterday]

Re: Adding Power Trim

Not to dispute the tech but, that just doesn't sound right. The pump is outputting the same volume of fluid to each cylinder. The larger cylinder will take longer to "fill" as the ram is extended and equalize the pressure of the smaller cylinder will it not? If you take that example to the extreme, say a 1" and a 10" diameter cylinder you can see what I'm getting at. Also the pressure exerted by each cylinder will be different because the piston surface areas are different. I don't really know how the pump operates but it doesn't sound logical to me to be able to use two different sized cylinders. Hope for your sake that I`m wrong. Good luck.

That's what I would have thought too but Im thinking there very well may be a crossover between the cylinder outputs in the pump. I say this because I was surprised when testing my cylinders, even if they were in different positions, one would run it's full travel, then the other would finish before the pump strained. That said, I'm sure as you've said, the pressure each cylinder would exert would be different, and in effect the smaller cylinder would be doing the vast majority of the work. It can probably work, but not exactly optimal.

My old Chrysler 85HP had a single hydraulic cylinder on one side, standard shock on the other, and it's single was smaller than both of the merc's. That would make me believe that as long as the tilt mechanism is working alright, one cylinder should handle the load. In this setup, the larger one would probably only provide "extra support" so to speak??? It will be interesting to see the outcome.

 

[mercurymang]

Re: Adding Power Trim

Any chance of salvaging the 850??

I intend to try. At this point, all I can say is that it isn't locked up.

 

[Yesterday]

Re: Adding Power Trim

I intend to try. At this point, all I can say is that it isn't locked up.

No compression tests yet hunh? The two I bought with 'excelent compression" were like this:
1) seized solid and lotsa rust in some cylinders
2) 140,70,70, untested. junkers... but the hydraulics and stainless prop were worth the money. It'd still be nice to have a backup power head.

 

[mercurymang]

Re: Adding Power Trim

2) 140,70,70, untested

:lol:

Well, I hooked up and ran the trim pump. I think the pump is ok but there are definitely some issues. I need to go through the bleed process first though. It did try to lift the motor for a bit but it's leaking pretty bad at one of the connectors. Ok, gonna go take another stab at it.

Edit: Kazek posted up the manual for these things and it has the bleed procedure on pages 24 and 25 but i'm having trouble reading it. Anyone else happen to have a clearer version available?

 

[Yesterday]

Re: Adding Power Trim

:lol:

Well, I hooked up and ran the trim pump. I think the pump is ok but there are definitely some issues. I need to go through the bleed process first though. It did try to lift the motor for a bit but it's leaking pretty bad at one of the connectors. Ok, gonna go take another stab at it.

Edit: Kazek posted up the manual for these things and it has the bleed procedure on pages 24 and 25 but i'm having trouble reading it. Anyone else happen to have a clearer version available?

I believe I might have something. also from my related thread. Credits to original poster.

 

[mercurymang]

Re: Adding Power Trim

Thanks. Perfect. Btw, is there a good method to fill up the reservoir? At first I tried just pouring it in but i think more made it on the ground than in the unit. Right now, I am sucking the oil up into a hose and then draining it into the tank. Any advice on a better way or is that pretty much it?

 

[Yesterday]

Re: Adding Power Trim

Thanks. Perfect. Btw, is there a good method to fill up the reservoir? At first I tried just pouring it in but i think more made it on the ground than in the unit. Right now, I am sucking the oil up into a hose and then draining it into the tank. Any advice on a better way or is that pretty much it?

I fill the reservoire, cap it, run the motor some, unscrew the cap and fill more - repeat till full. then bleed the cylinders, and once they're working fine, top up the motor/pump again one last time.

I too did make a mess, but had a drip pan under it. Biggest mess was opening the bleeder screws too far!
AFT shower much?!

 

[mercurymang]

Re: Adding Power Trim

Ok, I was bleeding it without putting the cap back on. I had the bleed screws completely removed but nothing was coming out of the bleed port. One issue I'm trying to figure out is the connector for one of the hoses is leaking pretty bad at the pump. It had a brass fitting that I'm not sure is supposed to be there but I can't seem to unscrew it. Can anyone tell me if this is supposed to be there or if it was added by the PO. Here's a pic.

 

[Yesterday]

Re: Adding Power Trim

Tht doesn't look familiar to me/mine.

 

[mercurymang]

Re: Adding Power Trim

Tht doesn't look familiar to me/mine.

That's what I was afraid of. When I tried to remove it, it didn't seem to want to thread out. I'm concerned that somewhere down the road, someone boogered up the threads and tried to fix it.

 

[mercurymang]

Re: Adding Power Trim

Ok, I think I'm getting somewhere. I re-attached the hoses and was able to stop it from leaking and got the port cylinder to bleed. I have a question. What is the knob on the pump for. Is it supposed to be turned all the way to the left, all the way to the right or in the middle?

 

[Yesterday]

Re: Adding Power Trim

Ok, I think I'm getting somewhere. I re-attached the hoses and was able to stop it from leaking and got the port cylinder to bleed. I have a question. What is the knob on the pump for. Is it supposed to be turned all the way to the left, all the way to the right or in the middle?

It's a reverse lock on/off valve. If I recall, full cranked to the right is on, full crank left is off. It's a manual bypass of sorts.