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 Posted: 07-01-2019 05:39 pm
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TommyV9
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I put a lot of work into my 74 JH over the weekend. I replaced the rubber brake hoses with braided steel. The body of this car has minimal rust, but every single fastener fought me the entire way. I also changed out the the cam cover gaskets and replaced the MC. It doesn't seem like that much when I write it down but it took me a lot of hours in a hot garage. Thank goodness I don't have to make a living doing this!

Now I'm trying to change the cam belt. I got the old one off and removed the crank pulley. (Edit: not necessarily in that order:) ) I had to remove the radiator and shift the oil cooler to get it done with the gear puller I had. I determined that my timing is 115/115, but my friend Jeremy convinced me to leave it alone and get it running then go back and change it later (one thing at a time). This is good advice. The stud for the tensioner backed out of the block rather than the nut coming loose, again, lots of corrosion. The tensioner and is stuck in the block. Do I just put a gear puller on it and pull it out? I have the twin bearings from Delta to rebuild it, but don't want to do something stupid, looking for some help.

TIA
Tom

Edit: not sure why the photo is rotated from what I saved.

Attachment: IMG_6820.jpg (Downloaded 42 times)

Last edited on 07-01-2019 06:06 pm by TommyV9

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 Posted: 07-01-2019 06:07 pm
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TommyV9
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BTW, here is my a pic of my cam pulleys with the crank at the TDC mark:

Attachment: IMG_6839.jpg (Downloaded 42 times)

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 Posted: 07-01-2019 07:59 pm
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TommyV9
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Ok, because I'm impatient and it rained before lunch and cooled down, I went home and used the puller, removed the tensioner, pressed out the bearings, pressed in the new ones, reinstalled it (with the stud hole on the top, tensioner pulley closest to the crank so I can tension by turning it counter clockwise - thanks for all the previous posts on this!) and got the belt on with all my marks lined up. I probably should pull the plugs (again) and rotate the engine twice to make sure my marks still line up.

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 Posted: 07-02-2019 06:35 am
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Esprit2
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Tom,
Well, it sounds like you got it taken care of without any help. But for future reference...

The tensioner's eccentric hub doesn't pilot into the block. Instead, it slips into a boss at the top of the front main seal housing (see attached JPEG). Since the stud had already backed out, you could have simply unbolted & removed the seal housing, then worked more conveniently at a bench.

Whenever you replace the timing belt, also evaluate the front main seal and the water pump. if they need attention, it will never be more convenient than when you have everything else stripped off the front of the engine to replace the T-belt. In this case, removing the seal housing wouldn't have been a liability, it would have been an opportunity to further leverage all the labor you were putting into the project anyway.

When you feel up to it, I do recommend that you re-time the cams to 110 Int / 110 Exh. Both cam pulleys will have to be removed and flipped over, front-to-back, before aligning the 110 timing marks (apply Anti-Seize to the pulley bores and cam journals during assembly). Once you get the whole timing belt thing figured out, it's not a big deal to make the change, and it really improves how the 907 runs. Well, that, more static ignition advance, and tune the carbs for best running/ power.

BTW, if you do go back into the belt again to re-set the timing, pull the tensioner back off and smear Anti-Seize on the:
1) bore in the front main seal housing's boss,
2) the eccentric hub's shank that fits into the seal
3) the stud & the eccentric hub's mating bore, and...
housing.
Keep the stud's threads clean and dry, and use a fresh Nyloc nut.

If you ever take the auxiliary pulley off, note that if it was correctly installed last time, then it was mounted with Loctite. It will require a puller and heat to remove it. Avoid aiming the torch flame toward the seal right behind the pulley. Wrap a wet rag around the shaft to mask the seal, then aim the torch forward from behind the pulley.

Regards,
Tim Engel

Attachment: 9XX Main Seal Housing - Front - Jensen Healey, Marked Up.jpg (Downloaded 36 times)

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 Posted: 07-02-2019 02:50 pm
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TommyV9
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Tim,

Thanks for the advice! I was on a timeline to get the car out of that part of the garage to satisfy SWMBO! The eccentric hub shank was stuck in the front seal housing's boss. I pulled the pulley with the bearings in it off and used the stud to press it back on after I did changed the bearings. I was planning to flip the cam pulleys and re-time to 110/110. Jeremy recommended I read your write up again and having seen it all in motion and checking my timing I finally understood why you flip the cam pulleys. When I do that, I'll put the anti-seize on as recommended.

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