135 Crossflow Powerhead Swap, Problem midsection interchange.

[RabboJens]

Found me a basterd engine.

Workin on my 76 evinrude 135. PH has internal damage and I bought a "135" cheap with shot gearcase, however on closer onspection one of the water tubes is damaged and will not seal with the pump. Also the powerhead is obviously a newer 140 or 115 bubbleback but it?s been intalled on the single thermostat midsection with one of the long hex bolt on each side left out. Pulled the heads and the engine PH looks both out and in to be in great shape.

So my question is can I run it like this on the other midsection or what?s the problem? I understand that I will miss two bolts but will something else be out of line enough to restrict water/exhaust flow internally?

Can i machine the missing holes in the newer block and install the missing bolts?

The motor seams to have been run with until something in the gearcase gave up.

 

[Faztbullet]

No it wont work as exhaust wont even line up...

 

[RabboJens]

That?s discouragin to say the least... so I need yet another midsection or I need to fit the newer motor? There?s not any fix around this? Thank you for your answer, I will pull averything apart and see for myself but any further input on the matter good or bad is apreciated.

I?m over in Sweden and the veteran outboard community is not as overseas so this forum has been golden to me. thnx

Reards Jens,,

 

[RabboJens]

Or if anyone has any thoughts on my original 76 135.

Here?s the full but compressed story.

Didn?t know much about outboards, got it running, had a warm seize, got it back, had bad water deflectors.
Changed em, got the heads sealed bad and had water combustion, after a bad milling I had to re-do it and ended up with a way up there compression.

I then thought well it still ran ok and I dont need all the ponys so I?ll run it easy, did some caustic zoda on the damaged cyl and removed broken exhaust deflectors. Got it running again but barely, thought the spark was weak so opted for better coils I also rebuilt and cleaned carbs. Plugs are wet, it start fairly ok but wont even stay of the warm up setting and dies when put into gear.

The only thing I haven?t yet to change is timer base and stator, both measures ok in ohms (i know that?s not the whole truth) but I?m starting to think that changing that over just wont do anything, or the motor will just spit those "new" parts out and seize up even worse. I have got most stuff for a complete rebuild along with the good 140-ish. Also have a functioning vintage trim/tilt unit two sets of correct controlboxes.

I have good tools and know my way around, time and money are the factors. Also I would so like to have the boat on the water thi summer... But I did get the 77 kawa jetski finished but that won?t hold the whole family.

I?ve read EVERYTHING looking for the quick fix for my perticular problem but of course I know it?s not likely to happen so last shot here, any thoughts??

Any help much appreciated.

 

[RabboJens]

Up and running.

75 midsection
80s powerhead
71 carbs.

Works perfectly, needs some carb tuning though.

 

[Faztbullet]

Must not be a 80's powerhead as nothing on blocks exhaust/water line up......

 

[Faztbullet]

Ok try these....Must not be a 80's powerhead as nothing on blocks exhaust/water line up......will leak exhaust into cooling area.

 

[RabboJens]

Hmm well I My powerhead dont look like the loser gasket, but the two middle volts Still wont line up. I looked for a part number during assembly bit couldnt find one. We're there any small changes in pH bases during the 70s? I'll ser if I can post a pic. Aldo determined I'm running early 70s 85 HP carbs. So I must be a bit low on hp.

 

[RabboJens]

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[RabboJens]

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Pics for compare, here its clearly visible the slight difference in the bolt and general apperance.

 

[Faztbullet]

Both of those are old style powerheads ........

 

[V153]

Both of those are old style powerheads ........

Correct. Mating surface is different well as bolt spacing.

On the post '77 one's that is.

 

[RabboJens]

ok but they are close in years? I wonder what opted for that small change.. I checked the parts list and I couldn?t find different exhaust adapters that would fit them. Do you know which is the oldest?

 

[Faztbullet]

There is no difference as both are the same. They use same midsections and gaskets...must have buggered threads in hole or bolt passages are scaled up