Crank swap possible?

A place for all your Diablo Rouge Questions or just a place to shoot the bull about those little Red Devils.

Re: Crank swap possible?

Postby jayvee43 » Thu Nov 12, 2015 7:38 pm

Roy Teske wrote:Hi Jesse
Measured an NOS crank I have and I get .018" clearance.... rod to crank side clearance.
Hopethat helps.
Roy


Thanks Roy. Yes that helps.

OK, I tryed the parrallel method. I made progress. I am now at 003" on the mag side, (at the very tip of the long end where the run out is most obvious. And .001 1/2 on the PTO side.

Here's a video I made quickly tonight.

https://youtu.be/sNiL5HSgVgM

I think I got it. :o
1971 Snowbug
1967 Diablo rouge 500
User avatar
jayvee43
 
Posts: 172
Joined: Sat Nov 15, 2014 8:45 am
Location: Renfrew, Ontario

Re: Crank swap possible?

Postby fap67 » Thu Nov 12, 2015 8:30 pm

Here's more food for thought. As you press the crankshaft halves together to decrease connecting rod sideplay, you are also moving the main bearings (which aren't installed yet) closer together. This is going to effect how the crankshaft is going to fit into the case. It seems to me that this is an important measurement too. Just a suggestion.
User avatar
fap67
 
Posts: 220
Joined: Tue Oct 06, 2009 5:02 pm

Re: Crank swap possible?

Postby Schoobytwo (Bruce) » Thu Nov 12, 2015 9:40 pm

I pulled a NOS crank off the shelf tonight and it too measured 0.018" rod clearance. So I think that is a good answer.

Regarding those speedi sleeves, they push on very easy. Just use a hollow pipe to rest up against the speedi sleeve collar and a couple easy taps with a dead blow hammer slides them right on. I typically put them on when the engine is together just before I put the seal plates back on. I press them on and just leave the collars on them. The collar ends up behind the plates.

Frank, you do make a good point about the bearing centers. The engine case halves are made such that one of the bearings has room to float and that makes up for expansion of the different metals.

Good conversation guys. I know there are a lot of people watching this post, so thanks for sharing everyone.

Bruce
Too many Diablos and parts to count.
Yamaha Apex (it outruns the Diablo for sure)
Yamaha 600 SX
User avatar
Schoobytwo (Bruce)
Site Admin
 
Posts: 1710
Joined: Fri Feb 22, 2008 12:47 am
Location: Sobieski, Wisconsin

Re: Crank swap possible?

Postby jayvee43 » Sun Nov 22, 2015 7:33 am

Alright! :D

It took a while and a lot of patiance, but in the end i got it to .0005 That's less than 1/2 a thousandth of an inch.

How I got there is very much by desperations. i took my 0.018" inch feeler gauge, and saw that it was still loose in the connecting rod to crank. So in desperation, I took the whole crank, put in the 20 ton press, and using an over size socket i firmly pressed on the two crank halfs until I heard it move. (My feeler gauge was firmly squeezed, but not stuck) Lucky me.

I taught this was it, I put it back in the jig, and VOILA! less than a thousandth of run out.

CONCLUSION: Yes it is possible to swap crank parts in these motors. Just plan on being patient and have yourself s a plan of attack and it can be done. If I was able to do this in a "tempo" tent. I'm sure anybody can do this now.

I hope this inspired a few that also were wondering. :?

All you need is a jig and a set up like the one Bruce and I have.
Image

I already put the rebuild crank into the engine, I must say this: I am feeling a whole lot better knowing the condition of the crank rod, bearings and tollerances. Thank you everyone specially Roy for your measurements and Bruce for your input measurements and advices and IDEAS!!!.

Here's the rebuild short block:
Image
1971 Snowbug
1967 Diablo rouge 500
User avatar
jayvee43
 
Posts: 172
Joined: Sat Nov 15, 2014 8:45 am
Location: Renfrew, Ontario

Re: Crank swap possible?

Postby jayvee43 » Mon Nov 23, 2015 5:15 pm

Well, There it is.

Today I was able to spend a good amount of time in the shop. I wanted to put the engine back into the tractor.

Well, after nearly 7 hours, I managed to pull it off. The engine is better than ever.
Here's the list of what I did swap.
I used the donor motor's Cylender, piston, rings, wrist-pin, clips, wrist-pin bearings and of course I used the connecting rod and lower rod bearings.
New crank bearings, and new gasket set, new spark plug and carburator kit. All in all, this engine is no longer the same RUSTY mess I purchased last year.

Here is a few pictures and a quick video of this afternoon. Sorry about the crappy video once more guys.

https://youtu.be/DIFstJgwvy8

Image

Also, lets see who notices:
Image

Thats it for me for this thread, I am now moving back to my original Diablo Rouge 500 complete overall.

follow me on this thread if you want to see some more.
viewtopic.php?f=3&t=1479

Thanks all who have helped me to this point.

Jesse
1971 Snowbug
1967 Diablo rouge 500
User avatar
jayvee43
 
Posts: 172
Joined: Sat Nov 15, 2014 8:45 am
Location: Renfrew, Ontario

Re: Crank swap possible?

Postby Roy Teske » Mon Nov 23, 2015 8:33 pm

Great stuff Jesse!
I enjoy following your restoration. Time for me to get my Diablo ready to go. Just finished scanning pictures from Larry's albums and will start putting them together soon. See you on the snow this winter.
Roy
User avatar
Roy Teske
 
Posts: 226
Joined: Mon Feb 25, 2008 7:29 pm
Location: Gatineau, Quebec

Re: Crank swap possible?

Postby Schoobytwo (Bruce) » Tue Nov 24, 2015 9:51 am

Very good post Jesse. I think we all learned from your post and it was an enjoyable post to follow.

Thanks for taking the time to share!

Bruce
Too many Diablos and parts to count.
Yamaha Apex (it outruns the Diablo for sure)
Yamaha 600 SX
User avatar
Schoobytwo (Bruce)
Site Admin
 
Posts: 1710
Joined: Fri Feb 22, 2008 12:47 am
Location: Sobieski, Wisconsin

Previous

Return to Questions & Discussions about Diablos

Who is online

Users browsing this forum: No registered users and 1 guest

cron