90hp v4 60 degree crank bearing issue

[Thriller1980]

Hello to all of you. I love this forum, this is my first post, I don't think this has been asked before but I I won't be surprised if it has. I am rebuilding my 95 Johnson 90 hp 60 degree looper due to a low compression in #4 cylinder. Things I have found wrong with it since closer inspection are, a missing roller sleeve on starboard throttle body cam affecting link and sync, 4 leaking float bowls (fixed), 1 cylinder was running hotter than the other, compression 128-132-125-82. Different rtv colours on heads (alarm bells), cracked crankcase cover at alignment taper pin, crank bearings spun a little due to dowel pins not aligned on last assembly, corrosion on cylinder head especially at the thermostat interface and at the exhaust port to head on #4 bore hence the low compression and a few other minors.

My question to you is how do I align my crankcase and cover with crack at taper pin hole in the cover and what is the part number for the check valve located under the crank split bearing halves? The stainless button from the valve manage to get lodged between the case and the bearing halve! Quite a sight to see, I didn't expect my rebuild to have so many obstacles.

One more question is forged or cast?

Thanks everyone who offers advice.

 

[Faztbullet]

Re: 90hp v4 60 degree crank bearing issue

a missing roller sleeve on starboard throttle body cam affecting link and sync, 4 leaking float bowls (fixed),

Common problems with the 60? motors, roller is problem on all the engines....

cracked crankcase cover at alignment taper pin, crank bearings spun a little due to dowel pins not aligned on last assembly

You can get around the taper pin problem but are the bearing locating pins pushed down in block? These have to protrude to lock race in place.

One more question is forged or cast?

Crankshaft is cast as are stock pistons....

 

[Thriller1980]

Re: 90hp v4 60 degree crank bearing issue

Here is a picture to help with my original post.



Thanks for your input.

 

[Thriller1980]

Re: 90hp v4 60 degree crank bearing issue

So I have the part number of the check valves. 0437773, I found it on a later model parts list.

Now all I need to learn is how to realign my cases with the cracked taper pin hole?

 

[Faztbullet]

Re: 90hp v4 60 degree crank bearing issue

To remove alignment pins, braze a rod to it, and pull it out after reheating block, then you can reinstall(after cleaning it up)it using a bearing half to set it at proper depth or order new pin(#304178). The tapered alignment pin at top left of block need not be used if cracked, just install front crankcase half and bolts just snug, then check that the mating half are flush on top of block by front seal as these are machined last after block is line bored. Tap the front half with rubber mallet to algin and when front/rear cankcase is flush, tighten the bolts to torque settings. This only works on a matching block.

 

[Thriller1980]

Re: 90hp v4 60 degree crank bearing issue

To remove alignment pins, braze a rod to it, and pull it out after reheating block, then you can reinstall(after cleaning it up)it using a bearing half to set it at proper depth or order new pin(#304178). The tapered alignment pin at top left of block need not be used if cracked, just install front crankcase half and bolts just snug, then check that the mating half are flush on top of block by front seal as these are machined last after block is line bored. Tap the front half with rubber mallet to algin and when front/rear cankcase is flush, tighten the bolts to torque settings. This only works on a matching block.

Thanks for the info Fastbullet. Taper pin removed, parts cleaned and inspected. now it time to get all the bits I need and put her back together. Any mild performance parts or modifications I could consider?

I've heard the ficht reed sets make improvements and to clean up the intake etc. What's you thoughts? not rushing the rebuild.

 

[Faztbullet]

Re: 90hp v4 60 degree crank bearing issue

I've heard the ficht reed sets make improvements and to clean up the intake etc.

The ficht reeds make it idle a tad better and more responsive but very little hp gain....

 

[Thriller1980]

Re: 90hp v4 60 degree crank bearing issue

Anyone with parts for my build in brisbane australia please let me know.
or a 115 that needs a rebuild.

thanks