Author Topic: 750 primary chain tensioner R&R  (Read 2714 times)

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DH

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750 primary chain tensioner R&R
« on: December 09, 2013, 08:17:41 pm »
Is it possible to separate the lower half of the engine case
from the upper half WITHOUT removing the cyl/head/cam and
pistons? And if so, will anything else interfere with getting
the primary tensioner out? This is a rookie question I know,
but I've never been in a 750 lower case before. :P

Offline goldarrow

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Re: 750 primary chain tensioner R&R
« Reply #1 on: December 09, 2013, 08:40:59 pm »
I've read that you can. 
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Offline mec

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Re: 750 primary chain tensioner R&R
« Reply #2 on: December 09, 2013, 10:22:29 pm »
you can

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Offline MCRider

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Re: 750 primary chain tensioner R&R
« Reply #3 on: December 10, 2013, 06:34:38 am »
YEs you can. I'll expand. Get the engine out. Turn it over. (before or after) remove the engine side covers, clutch cover, tranny cover, alt cover. (before and after) remove all bolts holding the cases together. Some come down from the top, some go up from the bottom. Some are hidden in the starter compartment and drive sprocket compartment.

Then the bottom case will lift off the top case. It will contain 1 shaft of the transmission and ... the primary chain tensioner.

This is first hand knowledge as I'm sure it is for MEC and others as well.
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DH

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Re: 750 primary chain tensioner R&R
« Reply #4 on: December 10, 2013, 07:10:50 am »
Thanks guys. I wasn't sure, and couldn't remember if any of
the camchain tensioner components would interfere or become
dis-located. Now I know :).

Offline bjbuchanan

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Re: 750 primary chain tensioner R&R
« Reply #5 on: December 10, 2013, 07:43:06 am »
One bit of advice from someone who went in the first time just a little bit ago. Don't overlook these half rings that locate the side to side movement of the gear shafts (can't think of term). I had broken piston rings floating around and originally thought they were them until I smartened up

Splitting them isn't tough tho. I had to take the advancer plate off too, they tie upper/lower together. Mark the plates location first for easy reassembly
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DH

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Re: 750 primary chain tensioner R&R
« Reply #6 on: December 10, 2013, 10:40:10 am »
One bit of advice from someone who went in the first time just a little bit ago. Don't overlook these half rings that locate the side to side movement of the gear shafts (can't think of term). I had broken piston rings floating around and originally thought they were them until I smartened up

Splitting them isn't tough tho. I had to take the advancer plate off too, they tie upper/lower together. Mark the plates location first for easy reassembly


And maybe change any seals too, eh?

Offline MCRider

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Re: 750 primary chain tensioner R&R
« Reply #7 on: December 10, 2013, 02:09:30 pm »
One bit of advice from someone who went in the first time just a little bit ago. Don't overlook these half rings that locate the side to side movement of the gear shafts (can't think of term). I had broken piston rings floating around and originally thought they were them until I smartened up

Splitting them isn't tough tho. I had to take the advancer plate off too, they tie upper/lower together. Mark the plates location first for easy reassembly


And maybe change any seals too, eh?

IF they weren't leaking before, I'd just leave them on their shafts and reuse them.
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DH

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Re: 750 primary chain tensioner R&R
« Reply #8 on: December 10, 2013, 06:30:14 pm »

IF they weren't leaking before, I'd just leave them on their shafts and reuse them.
[/quote]


I agree, but mine are originals, so I figured it'd be easier with it apart to change 'em.
What kind of sealer do you use between the seals and case? Anything different
than what's between the rest of the case surfaces? ( I'm gonna use Hondabond)

Offline MCRider

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Re: 750 primary chain tensioner R&R
« Reply #9 on: December 10, 2013, 06:47:21 pm »
Sure, can't hurt to change them.

Use a non-Hardening Elephant Snot type product like Gasgacinch. Every manufacturer has their own. Apply it, let it get tacky in a few minutes then assemble.

I think Honda Bond has different flavors. You'll want to stay away from anything with silicone in it. It hardens, flakes off and is known to clog oil holes with disastrous cam twisting results.

Good for gaskets and non-gaskets surfaces.
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Offline slyguy

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Re: 750 primary chain tensioner R&R
« Reply #10 on: December 10, 2013, 08:00:50 pm »
I'm kinda torn between renewing the tensioners or not? Don't have alot of money and the tensioners seem to still be quite plyable/soft and look perfect..even though they're 42 yrs old (12k) I suppose I could always use them on another I have? Thing is, arent those tensioners like $125.-$150. for the pair, and hard to get?

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 750 primary chain tensioner R&R
« Reply #11 on: December 10, 2013, 09:03:48 pm »
Only need ONE primary chain tensioner and Honda discontinued them recently.
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Offline slyguy

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Re: 750 primary chain tensioner R&R
« Reply #12 on: December 11, 2013, 08:20:29 am »
I was thinking primary and camchain tensioners. where might I find these?

Offline flybox1

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Re: 750 primary chain tensioner R&R
« Reply #13 on: December 11, 2013, 09:33:00 am »
NOS can be found on ebay for a pretty penny, but CycleX has their 'better than OEM primary tensioner" about 1/3rd the way down on this page...
http://www.cyclexchange.net/Engine%20Parts%20Lower%20End.htm
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Offline slyguy

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Re: 750 primary chain tensioner R&R
« Reply #14 on: December 11, 2013, 10:08:23 am »
Thanks, good to know!

Offline SKTP

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Re: 750 primary chain tensioner R&R
« Reply #15 on: December 11, 2013, 10:21:38 am »
I will be doing this soon as well...fun times :)
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: 750 primary chain tensioner R&R
« Reply #16 on: December 11, 2013, 11:26:14 am »
As for cam chain tensioners, I'm thinking you can still go Honda. Or there is CycleX also with his new design or the KA Performance is available just not sure from who.
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DH

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Re: 750 primary chain tensioner R&R
« Reply #17 on: December 11, 2013, 12:15:23 pm »
Those CycleX parts look tantalizingly good.  8)