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View Full Version : Question on Timing Belt Change Issue - Bart?



johnnyapollo
04/19/2012, 03:41 PM
I started the water pump and timing belt service as outlined by nfpgasmask here: http://isuzugeek.org/howtos/tbelt/tbelt.htm

Everything was going swimingly - rotated the belt several times and ligned up the pulley marks on each side and bottom, everything lined up to a Tee. Even the dotted line was in the right place. Removed the tensioner and expected the cam pulleys to pull towards the center (12 O'clock) - instead they pulled apart. So the passenger side pulley is now at about 8 O'clock and the driver side pulley at almost 3 O'clock.

My first instinct was to pull them back to the marks, aligning pulley, line and mark only pulling them together instead of apart as indicated in the write-up - but now I'm hesitant to do so as it could make things really off. Thoughts on that or should I just try it?

-- John

johnnyapollo
04/20/2012, 05:28 AM
Anyone?

SlowPro48
04/20/2012, 07:11 AM
Just do it. Given the old belt was intact and everything was lined up before you loosened the tensioner, if you have NOT rotated the crankshaft or cam pulleys after you removed the belt all you have to do is pull them back to the marks, clip them, line up the marks on the crank and pull the pin on the tensioner. The relationship between cams and crank will be maintained and you'll be good to go. This horse has been flogged a few times (sorry!) but bottom line is the engine is happy whether you line it up per Isuzu's instructions or per Bart's intructions.

It would still be prudent, however, to do as the manual says and rotate the engine by hand a couple revolutions to make sure there's no interference before you put the spark plugs back in and fire it up. Better safe than sorry!

MSHardeman
04/20/2012, 07:55 AM
When I did my timing belt change, per Bart's instructions, I seem to remember one of my cams sprang to the 12 o'clock position, but the other jumped to the 3 o'clock position. I think it all depends on how the valves are pushing on the cam at the time you release the tensioner.

Like SlowPro said, as long as everything was lined up when you took the tensioner off, and you haven't rotated anything, then when you line everything back up it should all work out just fine. DO rotate the motor by hand a few times to make sure that everything is happy before you turn the key.

johnnyapollo
04/20/2012, 09:27 AM
Thanks guys. When I looked at the videos it seemed to be the same message (although they didn't jump in the videos - wonder why?). In any case going out now to complete.

-- John

nfpgasmask
04/20/2012, 09:37 AM
I wish I had a better answer for you, but my pics and instructions are exactly what happened when I did mine. Now, what the others are saying makes sense, you will be fine since your timing is not off. Just do not rotate the crankshaft while the belt is off and you will be good to go once the new belt is on.

Bart

IndianaVX
04/20/2012, 07:36 PM
John, yes you should be ok, but if not..... I seem to remember 2 Isuzu grainy videos out there. One was pretty fuzzy on the procedure, and the other was like the sky parting and perfectly clear on the turning of the cams. Now, I can't remember exactly, but if you lost time completely, you do line up the cams on the marks, ( here is where My memory fails me) but the driverside cam gets turned just a bit more til it snaps in place. If I ever get on my computer again, I will try and post both of the videos I have. Good luck! I hope you have it running before you read this.

IndianaVX
04/20/2012, 07:39 PM
Argh, what's the point of auto correct, if you have to correct the auto correct???

Anyway, above post should read Isuzu TRAINING videos, not GRAINY video....as memory serves, video quality was pretty good!

johnnyapollo
04/20/2012, 08:13 PM
Update: Put her back together and she fired up like a champ. Ran fine for a bit then threw a code - uh oh - P0104. Looked it up and it read as a MAS issue - checked things again and realized the sensor wasn't plugged in. After clearing she ran fine. I haven't moved her yet as I wanted to top-up the tranny first - I'll do that first thing in the morning. Thanks for everyone's help - it's great having a few voices to assure you once things don't go exactly like the instructions...

I'm writing everything up as a blog post - I did have a few issues (mostly related to the crappy eBay kit I used - more on that later)...

-- John

blacksambo
04/21/2012, 08:56 PM
The OEM kit is the only way to go.

johnnyapollo
04/22/2012, 05:42 PM
Here's my blog post on the experience:
http://vehicross.blogspot.com/2012/04/about-time-for-timing-belt.html

-- John