Isuzu SUV Forum banner

UNIQUE and strange cam timing problem 99 3.2

8K views 21 replies 3 participants last post by  camposrf 
#1 · (Edited by Moderator)
Here goes. 1st off a BIG thanks to Buster on here- Due to his diligence I CAN say that a 99 Rodeo trans. WILL work in an 02 Axiom IF the connector is rewired correctly- with NO funny shifting issues....

NOW on to the real issue- I have another 99 Rodeo that I had to replace a cam pulley bearing in as it was sticking badly...I discovered this replacing the timing belt when the water pump seized up at 256k. This thing runs perfectly normally, thanks Isuzu for using good steel back then...

Now- the LH cams are out of time with each other. I have searched here high and low for 2 days and seen some great info..
BUT I have a unique problem it seems. On my LH bank (drivers side) both cams, intake and exhaust, have 2 dots on them side by side.....with 1 dot filled in. There are no other markings on the cams whatsoever. none. the cams both look like this:

cam ref 2 MY cams left side.png


I know that's a drawing, but both my cams have two dots right beside each other and nothing else on the cams. One of the dots of each goes all the way through, the other of each is just an indentation but does not go all the way through.... the cam pulley drive gear has the two normal reference dots. That at least seems normal.

From what I have seen- the cams should have two dots on each, in a row, NOT side by side. As I said earlier, there are no other markings on the cams whatsoever... I have spent 3 days now searching for a reference to time this thing, but have found nothing definite as these cam marking aren't like the typical ones it would seem.... typical meaning 1 dot each on right side, 2 dots (in a row) on left side. As mentioned, my two cams on the left side only have two dots side by side with one not going all way through on each>

Any ideas on how in the world to time this prior perfectly running 3.2?

Thanks! and thanks once more to Buster for that tranny solution I mentioned above!
 

Attachments

See less See more
1
#2 ·
The right and left exhaust camshafts are identical, the exhaust camshaft drive gear has a single dot and a double dot stamped into the gear face When the exhaust camshaft is installed in the left bank the double dot is used for alignment. When the exhaust camshaft is installed in the right bank the single dot is used for alignment. The intake camshafts are bank specific, the left bank camshaft drive gear has a double dot and the right bank camshaft drive gear has a single dot. The idler gear that mates with the camshaft drive gear has two single dots spaced 60 degrees apart.
In the attached exhaust camshaft image the drive gear double dots can be seen in lower right. How does compare to your exhaust camshaft.
 

Attachments

#3 ·
Thanks Buster..that arrow on the diagram shows something I didn't even know to look for. I'm thinking that they will be 180 degrees opposite of the double indents top side as shown above- on my left bank cams, there doesn't appear to be any double dots- I'll look again, they must be there hopefully- and if they are/ problem solved.
 
#4 · (Edited by Moderator)
Ok- I lined up the two small holes in the drive pulley cam gear to the two TINY holes almost impossible to see unless surgically clean cams---- sure enough- one also faintly says LI, and the other LE.... I have timed both cams EXACTLY to the two small inline holes. It is an absolutely perfect match. Here's the thing- The lobes still do not match the timing diagram (below) on the left bank no matter how many rotations I make. They should be at 11 oclock and 1 oclock, facing each other according to below. They also do not snap into position when turning, though each cam is not binding and will snap into position with the timing of the cams in a different location. I remember when I first took the cam pulley drive gear out, I marked the cams before I removed the valve cover and took at look inside... The cams were in time then. I did this for two reasons- 1st, there was a LOT Of friction in turning the cam pulley left side- it would barely move without a LOT of torque.. 2nd, when I did the timing on the Axiom I have, the left side snaps into place as normal when putting the pulley mark to 9 oclock, and then turning just a bit more to 12 oclock..

This tells me, because the vehicle ran perfectly, that there must be some kind of alternative timing setup?

I would take a pic and put it here, but instead let me just say that the two in line timing dots on each left bank cam are pointing EXACTLY to the two small holes in the cam pulley drive gear? It seems like it's timed exactly as it was before I put the new bearing in... This is a very weird situation indeed-Any idea what gives here?
Rodeo timing pic.jpg
 

Attachments

#5 ·
The drive gear with the dots is secured to the camshaft with a press fit and an alignment pin that fits into the gear and the camshaft. The pin and the slot in the drive gear are not visible until the gear is partially removed from the camshaft. Occasionally the pin shears off allow the camshaft to get out of alignment. The dots will still match but the camshaft is not in the correct position.
 
#7 ·
Apologies for the 2 separate posts for the pics--- not sure how to put them both in one post

Here's the pic of my cam lobes, clearly not where they should be

The cam pulley gear and shaft are new off another new head... so I don't see how the pin inside can be broken, unless I'm not seeing something......
 

Attachments

#8 ·
I think I've got this understood- Buster, you're saying that one of the cam gears is spun on the the camshaft with a broken pin inside? Would this happen if the water pump pulley froze? ... because that's what broke to need repair.

If so, seems like that's the only thing that fits here-

If that's the case, can I just Weld the gear in the position it spun to and time it according to lobe position instead? That would work if welding would be enough....the gears seem super tight on both camshafts..

If no... I have another new set of camshafts- can I replace both camshafts with new and the valve lash will still be the same .... as in the two camshaft would have to be identical in lobe size to not cause a difference in valve lash?

Thanks infinity Buster- you skills must be in very high demand wherever you are :)
 
#13 ·
It continues- can't believe it, but here's what it is

Put the new pin in the cam, and put the gear back on--- VERY diligent to make sure everything is precise.... got it alll re-assembled and then went to the magic moment- started right up, but running a bit rough, check engine light flashing continuously, and making a "tic tic tic tic" sound continuously- not super loud but very noticeable. I was so so careful to time it right also.... used the same cam and all surgery room clean--- I can understand why it might be running rough if I got it off a tooth- but why the tic now? what a kick in the shin- thought I had this nailed... Any ideas?

Thanks,
RJ
 
#14 ·
The flashing CEL indicates a severe misfire condition which is why the engine is running rough. A misfire could be ignition or a mechanical problem. Run a compression test and check or replace the spark plugs.
 
#15 ·
Thank you Buster for the recommendations; here's the situation now... found out that the cam I repaired was not quite perfect with the repair, and that threw the time off just a bit. I went ahead and put a new cam in this morning, carefully as always being as I VERY much dislike doing things twice if I can avoid it... anyway started it up ran great; also no more loud ticking...so I put it all the way back together.... ONLY TO DISCOVER when it was totally assembled that it runs pretty good still, BUT the tic is back.... so I'm thinking how could the tic be back if I didn't change the timing in the middle--- plan is now to move timing back and forth one tooth and see if the tic remains. Anyone have any suggestions on why the tick would be gone, then back in a 30 minute testing period; same timing? thanks
 
#18 ·
Thanks Buster.
Solution found- I had replaced the cam pulley drive gear and FORGOT to set each of the pre-loads on the cam gear- terrible loud clicking noise .... then with one preload set- half that clicking noise.... then with both preloads set- NO TICKING NOISE. Fantastic. Now I'm back up to normal- but, but with a P0113 code---- no code before...sooo I'm wondering if I messed up a sensor somehow..
 
#20 ·
rktsiens said:
(...) FORGOT to set each of the pre-loads on the cam gear (...) but, but with a P0113 code(...)
when I had this issue and I had no P0113 code while the cam was noisy. ( 3.5L 6VE1 Tick/Knock camshaft )

Buster28 said:
P0113 is an Intake Air Temperature (IAT) sensor problem. (…)
As Buster28 said about P0113, It should be the MAF sensor wiring (MAF sensor sense the air temperature too). In my case this connector is close to the air filter.

Looking for 99 rodeo engine picture I found this MAF sensor location, check this wiring near from the air filter.
 
#21 ·
Thanks for the help- Yep I found the problem- the connector wires for the little 2 wire sensor connector on the air inlet tube was not making contact when I attached it. Just had to take the 2 wires out and reinsert them into the connector the proper way-

Now- no lights on dash and no clicking sounds..... running perfect again at 256k - For all the faults of Isuzu (mostly post year 2k from what I've seen)they used GREAT metals. Thanks again to everyone for the help
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top