Evinrude 1977 85HP

dropbear68

Petty Officer 2nd Class
Joined
Jan 21, 2013
Messages
199
Im in the process of fitting my engine, i retrofitted from a volvo sterndrive to the Evinrude, whilst prepping for paint Ive noticed underneath the stern clamp one of the pipes to the tilt trim pump has been bypasses, a threaded end with the pip[e crushed has been fitte din the base of the pump Im guessing the trim side of things has flunked it, not knowing much about this particular OMC product, does this motor have the usual Preslite set up Id expect to see one ram for tilt and the the trim ram between the stern clamps? what is the common failure with the trim would it be pump related or ram related its fundamentally just a hydraulic system so maybe a blocked valve somewhere? would the trim unit be serviceable? would it be something someone of better then average mechanical apptitude could do?

Im going to do a tell tale conversion I read about on here and do some engine mods for a touch more ooomph, most of the bolts on these i imagine are imperial thread as i want to replace as many bolts as i can get to with stainless items, my last query is the water pump impellor its not going anywhere near the water without a new one fitted, are these easy enough to change with the electric box? any traps there to be wary off? million thank yous in advance.
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
That early trim system uses two outboard trim cylinders to function. It needs both in order to trim the engine when under power in the water. If you want it to function as designed, you'll want to replace the hydraulic line (pipe). You can have a look at all of the trim components by going to the factory website and examine their exploded parts diagrams for the trim system: epc.brp.com In addition to seeing the parts you need, the drawing shows how the components go together-helpful when repairing. There are two types of trim motors/pumps used interchangeably on this system. You can identify which you have by comparing the pumps visually with the one you have. Calco or Prestolite. This trim system has been out of production for probably 15+ years, so some of the parts you need may have been discontinued and are hard to find. Some folks buy another junk 85 hp engine of this era just for the obsolete trim parts. Also, an original factory service manual of this year would be useful, esp when working on this trim system. Check out this website: outboardbooks.com I ran one of these for a number of years on a 76 135 engine. While it looks unusual, it did the job just fine.
 
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dropbear68

Petty Officer 2nd Class
Joined
Jan 21, 2013
Messages
199
Ok, I have removed the blocking plug from the tilt motor and reconnected the pipe that was just cable tied to another, I dropped the lower pipe out of interest to check oil content and what I got was milky crud, so Im thinking a flush with clean oil is needed and test the system. My questions now is what type of oil to use, my old Chrysler with the same tilt pump used a straight 40 engine oil?, cant use auto trans fluid or plain hydraulic oil?
 

dropbear68

Petty Officer 2nd Class
Joined
Jan 21, 2013
Messages
199
I have removed the pump unit of the outboard Ill pull it down and clean it out and replace what bits I can, it could do with a good de corrode and some general love and detail, I have found a place with good stocks of trim tilt parts, all of what I will need anyway
 

dropbear68

Petty Officer 2nd Class
Joined
Jan 21, 2013
Messages
199
Ah Petty Officer now , I dont know how much clout a PO in the USN pulls but in the aussie navy a PO or a CPO is a force to be reckoned with lol
 

dropbear68

Petty Officer 2nd Class
Joined
Jan 21, 2013
Messages
199
I gutted the tilt pump, good thing I did, it would never have worked, the oil had literally turned to white grease, pipes were pretty much blocked, I stripped the lower pump section down and its much the same so something was leaking water into the system, Ill give these parts a good clean up with carby cleaner, go find a new lower seal that should see it work again, it only has one ram thats hydraulic so its just a tilt set up, although there is a second pipe with a rubber hose section I pulled this out , if it had trim what would it had been ram wise? this system is similar to my old 70hp Chrysler set up but she had trim, same pump/ motor anyway, I would like to replace the electric part of the motor with a new part
 
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