#1  
Old 07-27-2021, 04:05 PM
jrunner jrunner is offline
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Default OHC 6 Timing belt questions?

Hello I’m new here to this forum. I have a few questions about the ohc6 timing belt. What brand belt do you guys prefer using that is available ?

How often should the belt be replaced?

Are the ohc belts known to brake?

And if the belt brakes will the valves hit the pistons?

While r&r timing belt is there anything else that should be replaced while torn down?

changing the timing belt a difficult job?

What does PY stand for?

Thanks in advance.

  #2  
Old 07-27-2021, 06:14 PM
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Jeff Hamlin Jeff Hamlin is offline
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WELCOME, Both to PY and the world of OHC 6 ;-)

There are only a small amount of aftermarket belts available.
EGGE Machine & KANTER Auto were the main suppliers but I'm not sure they still carry them. EPAY is another source.

Theoretically, the belt could last the life of the engine per design.
The only things to kill a belt are oil, UV, and catastrophic failure.

The OE belt was tough as nails and could take a lot of loads.
I wiped a cam years ago and the belt didn't break but the sudden rotation stop tore several cogs off the belt.

This is a ZERO lash engine so NO the valves will not make contact with pistons.

As with any engine look for the obvious wear on all contact points and then decide if it needs replacing.

Changing the Timing Belt is not that hard of a task if you know the engine.

It seems to me you may not have a good service manual, If I'm wrong then forgive me. However, if you do not I suggest you seek out a good used copy of the 1967 version. It is one of the best throughout the 4 year run of OHC 6 engines.

Also, know that Gaskets are also limited and pricey.

Do all your research before tearing in.

I've attached a few pages from the SAE report on the OHC 6 that pertain to some of your questions.

And if in doubt ASK Away!!

Cheers.
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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #3  
Old 07-27-2021, 06:15 PM
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Jeff Hamlin Jeff Hamlin is offline
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Oh yea, PY=PERFORMANCE YEARS.

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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #4  
Old 07-27-2021, 06:29 PM
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Jeff Hamlin Jeff Hamlin is offline
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Oh and I almost forgot another good source for Parts and Information is Rob Egbert who now owns and runs WOODLAND MOTORSPORTS
Check out his Facebook Page;

https://www.facebook.com/Woodland-Mo...1129785127848/

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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #5  
Old 07-27-2021, 07:41 PM
Hokie1984 Hokie1984 is offline
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The cheapest source for the gaskets is Rockauto. It’s listed under valve cover and it includes the accessory ones. Last I checked they we under 8 bucks.

  #6  
Old 07-27-2021, 11:26 PM
jrunner jrunner is offline
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Quote:
Originally Posted by Hokie1984 View Post
The cheapest source for the gaskets is Rockauto. It’s listed under valve cover and it includes the accessory ones. Last I checked they we under 8 bucks.
Thank you very much for all the information.

  #7  
Old 07-27-2021, 11:27 PM
jrunner jrunner is offline
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Quote:
Originally Posted by Jeff Hamlin View Post
WELCOME, Both to PY and the world of OHC 6 ;-)

There are only a small amount of aftermarket belts available.
EGGE Machine & KANTER Auto were the main suppliers but I'm not sure they still carry them. EPAY is another source.

Theoretically, the belt could last the life of the engine per design.
The only things to kill a belt are oil, UV, and catastrophic failure.

The OE belt was tough as nails and could take a lot of loads.
I wiped a cam years ago and the belt didn't break but the sudden rotation stop tore several cogs off the belt.

This is a ZERO lash engine so NO the valves will not make contact with pistons.

As with any engine look for the obvious wear on all contact points and then decide if it needs replacing.

Changing the Timing Belt is not that hard of a task if you know the engine.

It seems to me you may not have a good service manual, If I'm wrong then forgive me. However, if you do not I suggest you seek out a good used copy of the 1967 version. It is one of the best throughout the 4 year run of OHC 6 engines.

Also, know that Gaskets are also limited and pricey.

Do all your research before tearing in.

I've attached a few pages from the SAE report on the OHC 6 that pertain to some of your questions.

And if in doubt ASK Away!!

Cheers.

Thank you very much for all the information.

  #8  
Old 07-28-2021, 06:41 AM
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Jeff Hamlin Jeff Hamlin is offline
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Thumbs up Glad to help.

If you're not already aware of our FB forum, check it out when you have a chance.


https://www.facebook.com/groups/1013971318683583/

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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #9  
Old 08-19-2021, 12:31 AM
jrunner jrunner is offline
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Default Ohc 6 timing belt questions?

Hello please help I have a few more questions. So I started tearing down my 68 and I only have a 67 service manual. My lower timing belt cover is shaped a little different by the acc drive gear than the picture in the 67 manual. Would the accessory drive gear Mark be lined up with the edge of the 68 cover?? Also I have the cam gear Mark straight up and the harmonic balancer at 0 and my distributor rotor pointed at number 1. I just realized that I did not pull #1 plug to confirm it was on tdc will check tomorrow. But. With the marks lined up as I have. the accessory drive gear mark is pointed straight up and I’m thinking this is wrong?? Does anyone have a picture of 68 timing marks?? I just purchased a 68 service manual today on epay not sure how soon it will get here. And. I’m also changing out my cracked driving me crazy leaking oil accessory drive housing for a nice rebuilt one from Rob over at Woodland Motorsports. Ok my question is what is your procedure for the gaskets on the acc drive housing?? I’m wondering because of the belt adjustment if I don’t get it right the first time?? Install dry?? My existing belt only has stamped 011 on it and my new continental belt has 98 cogs or teeth is this correct?? I haven’t removed the old belt yet. Sorry pictures are sideways.
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  #10  
Old 08-19-2021, 06:23 AM
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Jeff Hamlin Jeff Hamlin is offline
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Thumbs up From the '68 SM

The procedure is the same.
Looks like you have a small chunk out of the leading edge, this is the alinement point.

If your changing the belt, what I always do is set the Acc sprocket mark just below the edge of the lower timing cover,
this way when you slide the housing down to tension the belt the sprocket mark will roll up to the correct position.

(AMA Belt Specs; 98 Teeth. 1.032 - .954 Width. .500 Pitch.)
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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #11  
Old 08-19-2021, 06:47 PM
Hokie1984 Hokie1984 is offline
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The other thing I do is back off the crank a few degrees , install the belt and then rotate the crank to 0 degrees. This tightens up the right side of the belt ( looking at the engine) so all you have to worry about is the tension on the accessory drive side.

  #12  
Old 08-20-2021, 12:28 AM
jrunner jrunner is offline
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Great thank you Jeff and Hokie1984 I will use those techniques when I make it to that point for sure. I’m finding more problems during my tear down. I just got my water pump rebuilt today I think the gasket was blown a couple of the wp bolts were loose so I figure get it rebuilt now. Also yes my lower timing cover has a few cracks and missing chunks. Also my harmonic balancer looks like it’s had some rough nights see pictures. I’m now wanting to replace the crankshaft front seal it has been leaking too. Please I also have a question about that. Does the crankshaft sprocket just pry off?? And also looking in the manual installing the front crankshaft seal I don’t have that special tool any thoughts on other ways of pressing the new seal in?? You guys wouldn’t have an extra 68 harmonic balancer for sale would you?? Rob said I could get it rebuilt but mines got chunks missing and the bolt holes have been broken with studs welded in place plus the rubber is / looks brittle. Thank you for helping me I really appreciate your feedback and great advice.
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  #13  
Old 08-20-2021, 06:05 AM
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You will likely need a puller to remove your HB.
I would consider looking into possibly having yours rebuilt,there are a few well-known rebuilders DD come to mind;

https://damperdoctor.com/index.php?r...ormation_id=13

Might reach out to them to see if it's salvageable

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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #14  
Old 08-20-2021, 06:09 AM
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I have a 1BC '68 HB if it's of any use to you.

You might also concider placing a WTB for a better unit.

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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #15  
Old 08-20-2021, 06:14 AM
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Jeff Hamlin Jeff Hamlin is offline
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I just saw you do have a wanted post,
Might want to clarify you are looking for a 4BC HB.

cheers.

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When I die, I want to go peacefully like my grandfather did, in his sleep.
Not screaming like the passengers in his car.
  #16  
Old 08-20-2021, 05:00 PM
jrunner jrunner is offline
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Thanks guys I didn’t know there was a difference. I replied to the post adding the 4bc. I couldn’t see how to delete or ad to the post.

  #17  
Old 08-20-2021, 07:40 PM
Hokie1984 Hokie1984 is offline
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You absolutely need a harmonic balancer puller but after that I think the sprocket in fairly loose with a key holding it from spinning.

  #18  
Old 08-20-2021, 11:54 PM
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Hi guys thank you yes I got the balancer off and waiting to hear from John at Damper doctor for an estimated cost to rebuild my old hb. The lower gear came right off as soon as I loosened the belt. I also removed the crankcase cover seal. I ordered a crankshaft seal and timing cover seal a ways back from rock auto and both are too large timken 9845 and Skf 17286. Do you guys know where I can get the correct seal or the part number ?? Crankcase cover seal is what I need/ crankshaft seal. I looked at egge and kanter. Thanks.


Last edited by jrunner; 08-21-2021 at 12:00 AM.
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