Author Topic: Would you change this tensioner?  (Read 1556 times)

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Offline Magpie

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Would you change this tensioner?
« on: November 26, 2008, 05:35:18 PM »
Hi gang!
This was in a sandcast I'm rebuilding, I don't know the mileage on it. It looks quite good but is hockey puck hard and I don't know if it's supposed to be or not. It's also not really expensive, about $60, but why replace something that may be good?
Do you builders just replace the primary and cam chain tensioners as a matter of course in your builds?
Thanks!
Cliff.

Offline stresssolutions

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Re: Would you change this tensioner?
« Reply #1 on: November 26, 2008, 05:57:59 PM »
looks good to me.  It is, however the first one that I've ever seen.  Is it hard enough to chip?  Brittle, I mean.
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Offline Alan F.

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Re: Would you change this tensioner?
« Reply #2 on: November 26, 2008, 06:55:49 PM »
Being a sandcast (you're quite sure?) I'd spring for a new tensioner, new chain, heavy duty studs....

Offline Magpie

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Re: Would you change this tensioner?
« Reply #3 on: November 26, 2008, 07:02:49 PM »
Yes, it's a sandcast (10002**). Unfortuately I only have the engine not the bike. It will go in a 12/69 frame. I have new primary and cam chains for it gathered over the years. The tensioner wheel is not brittle just very hard. In the scheme of things it's a minor cost but................... I know, I know - don't skimp.
Cliff.

Offline Gregorymoto

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Re: Would you change this tensioner?
« Reply #4 on: November 26, 2008, 07:44:30 PM »
ya man replace it all save the old head studs so you can keep the bike complete.
Yep, i have issues with this sort of stuff.

Offline mystic_1

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Re: Would you change this tensioner?
« Reply #5 on: November 26, 2008, 09:03:55 PM »
Roller should be firm, but still somewhat pliable.  You should be able to dent the rubber with your fingernail.  Should be a matte finish too.  If it's rock hard or glossy (glazed looking) then I'd replace it.

New tensioner costs, what, $80 list?  ServiceHonda lists them just over $50.  Cheap insurance to just replace it if you have any doubts.

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Offline wrenchmuch

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Re: Would you change this tensioner?
« Reply #6 on: November 27, 2008, 05:49:02 AM »
 If that is an original tensioner then your engine hasn't been run much . The original 30 year old pieces are hard and not resilient anymore . The chains beat them up and break bits off . Looks like a mouse has chewed on it . At best the bits end up in the pan . The oil filter should stop the stuff before it gets to the head or main bearings . The oil pump screen is all that protects the pump and transmission . I had a piece of something block the left oil passage in my head . Wrecked the cam bearings , shaft , and rockers . I replaced all the rubber bits except for the end of the cam tensioner plunger ( not available). I suffer from oil blockage paranoia now . :( But I did get to rebuild my engine . Can't wit till spring . ;D
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Offline Magpie

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Re: Would you change this tensioner?
« Reply #7 on: November 27, 2008, 07:29:59 AM »
Wrench,
I think you just nailed it! Your OBP convinced me that replacing it may save the engine at some point. I was lucky enough it found me, now I better treat it nice.
Cheers,
Cliff.