Cam timing mystery?
06-22-2017, 03:46 PM
#1
Registered User
Thread Starter
Join Date: May 2006
Location: Cedar City, UT
Posts: 106
Likes: 0
Received 0 Likes
on
0 Posts
Cam timing mystery?
Kinda lengthy story so, bare (or bear?) with me.
Had the head on my 85 pu's 22RE rebuilt a few years back and the machine shop milled it a little too much so, I installed an adjustable cam gear to bring the cam timing back to where it needed to be. I should mention it has an Engine Builder 261 crawler cam and it ran great!
This truck is my daily driver/work truck and on my way to work one morning I lost all my coolant due to a major radiator rupture (plastic tank seperated from the aluminum core) and ended up overheating it and warping the head.
Replaced the head with another one I had rebuilt and added Engine Builder's oversize stainless valves and spring kit, luckily the bottom end and pistons/rings weren't hurt. Ran real good!
Well then, it started to make a bunch of racket from behind the timing cover.....turns out the tensioner block had worn through to the metal and was rubbing the chain!
Bought an OEM OSK brand kit and replaced the whole set up. Now here is where it gets weird!
I have done several timing chains so it was a no brainer or, so I thought!
Installed the guides, gears, chain (lined up the shiny links with the appropriate marks) and tensioner and buttoned everything up, stabbed in the distributor, started it and it ran like crap! It would only run with timing waaay advanced???
Thinking I had the gear a tooth off, I pulled the valve cover off to confirm I had the cam gear indexed correctly.....crank at TDC, cam dowel pin at 12:00, right where it should be! If i set the timing where it should be (5* btdc, 22RE) it barely ran and revved very sluggish like the cam was way retarded?? So, I tried advancing the cam with the adjustable gear and it made a huge improvement. So, I popped the gear off set it back to zero and advanced it one tooth/link, reset the ignition timing (it still likes a little more than spec) and it runs really good. So.....what the hell is going on? I tried calling Ted at Engine Builder to pick his brain but, his shop phone has had a busy signal for the last couple of days now.
I'm stumped guys! Anybody have any ideas/thoughts? I mean, it runs pretty good now but, something's not right!
Hans
Had the head on my 85 pu's 22RE rebuilt a few years back and the machine shop milled it a little too much so, I installed an adjustable cam gear to bring the cam timing back to where it needed to be. I should mention it has an Engine Builder 261 crawler cam and it ran great!
This truck is my daily driver/work truck and on my way to work one morning I lost all my coolant due to a major radiator rupture (plastic tank seperated from the aluminum core) and ended up overheating it and warping the head.
Replaced the head with another one I had rebuilt and added Engine Builder's oversize stainless valves and spring kit, luckily the bottom end and pistons/rings weren't hurt. Ran real good!
Well then, it started to make a bunch of racket from behind the timing cover.....turns out the tensioner block had worn through to the metal and was rubbing the chain!
Bought an OEM OSK brand kit and replaced the whole set up. Now here is where it gets weird!
I have done several timing chains so it was a no brainer or, so I thought!
Installed the guides, gears, chain (lined up the shiny links with the appropriate marks) and tensioner and buttoned everything up, stabbed in the distributor, started it and it ran like crap! It would only run with timing waaay advanced???
Thinking I had the gear a tooth off, I pulled the valve cover off to confirm I had the cam gear indexed correctly.....crank at TDC, cam dowel pin at 12:00, right where it should be! If i set the timing where it should be (5* btdc, 22RE) it barely ran and revved very sluggish like the cam was way retarded?? So, I tried advancing the cam with the adjustable gear and it made a huge improvement. So, I popped the gear off set it back to zero and advanced it one tooth/link, reset the ignition timing (it still likes a little more than spec) and it runs really good. So.....what the hell is going on? I tried calling Ted at Engine Builder to pick his brain but, his shop phone has had a busy signal for the last couple of days now.
I'm stumped guys! Anybody have any ideas/thoughts? I mean, it runs pretty good now but, something's not right!
Hans
