evinrude 70hp powerhead

[moey]

Hey there guys this is my first post hopfully 1 of many
Basically im getting back into boating and i have a full rebuilt evinrude 70hp engine number 70573e
It hasnt got a electric tilt trim but i found a bargain full motor
It is a evinrude 70hp 1985 model with tilt trim
My question is would my 1975 power head simply bolt direct on the 1985 unit
Thanks if i missed on any details needed let me know
Thankz guys

 

[emdsapmgr]

No, it won't. The 85 style is the newer style which fits snugly between the two transom brackets. Your engine is the older version that has two trim rams that mount on the outside of the two transom brackets. You can check this out on the original factory parts diagram website: epc.brp.com. The 75 trim unit is found under the accessories tab, the 85 is found under the normal engine diagrams. Your 75 style works well, but has been out of production for many, many years. Best thing would be to purchase a junk engine with a working old style trim unit, then install it on your engine.

 

[racerone]

The 1975 powerhead may fit onto the 1985 model.--------You need to look into the 6 bolts that hold the powerhead on.-----They went to bigger bolts on the later models.---Went from 5/16" to 3/8"

 

[moey]

Thanks for the quick reply guys i apreciate it
Im going to need to do some research about these bolt sizes
I looked at the powerhead gasket that sits between the exhaust unit and power head the 1975 gasket is the same as the 1985
I never new these powerhead would change so much yet they are very similar

Here is a picture of the lower unit and power head if that helps
I also have a picture of the 1985 unit that im looking to use if that help
It wont let me add photos from my phone i going to try on the computer later on

 

[racerone]

No need for pictures here.-----You might consider making sleeves to go over the 5/16" bolts to take up the slack if need be.

 

[willamettejeff]

Won't work. Driveshaft on 1975 had 4 splines going into power head, where 1985 driveshaft has more (15 if I remember right). Change occurred with 1984 model. You won't be able to set your power head onto the 1985 motor's drive shaft.

Need to find 1978 to 1983 motor either one already with T&T or purchase T&T unit and control box separately. Proper T&T unit was used from 1978 to1993 on all size J/E outboards. The Fast Strike T&T was introduced in 1994. Pre-1978 T&T units with the external rams are very hard to find.

 

[flyingscott]

Drive shaft on an 1985 model has 4 splines. The newer drive shaft was not introduced until 1989. It will work as long as the driveshaft is a match.

 

[willamettejeff]

I was mistaken in my post. flyingscott is right. Sorry about that, but still may not fit as crankshaft and driveshaft P/Ns changed between 1975 and 1985. Depends on what changes were made to those parts on whether will fit.

 

[moey]

Maybe ill get the seller to send me a picture of the driveshaft as its already off
Then ill post it up see what you guys think thanks

 

[racerone]

???---It will fit as per post # 3 and the driveshaft splines on the 3 cylinder was the same from 68 to 1988 models..----Bolts may be bigger and depending on whether yours is an early 1975 or late production.---You may have to make minor changes on the the shift linkages too.---It is all doable.

 

[moey]

Thanks for the replies guys
It is defently the same spline he sent me pictures
As for the bolt size im going to measure my bolts if they are smaller wouldnt they still work as in using my same powerhead
Dont the bolts go straight through the bottom housing into the head

 

[racerone]

Again take heed of post # 5---- all there for you to consider.------The bigger diameter bolts are shown to be used from 1985 to the last model made in 2001.------- The sleeves would prevent the powerhead moving side to side.---The sleeves would align the crankshaft and the exhaust housing / lower unit too.

 

[moey]

Thanks again
Ill will post back when i have a outcome if anybosy else runs into the same issue