Head Rebuild @ 250K Miles

[TTurner161]

Rumor has it the 2.3 (and the 2.5 if its based upon the same design) is next to impossible to line up timing-wise. Always about a half-tooth off. Not sure why... I've heard people say just turn the cam sproket 360 degrees to fix it, but wouldn't that just put the cam back in exactly the same place?

Yeah they dont line up quite perfectly like you said, I guess as long as its as close as you can get it.

There is nothing whatsoever difficult about timing the 2.3/2.5 Lima engines. The only RBV engine I've heard of being a problem is the SOHC 4.0.

Well its not difficult, its just the marks aren't all to accurate. I mean the timing marks are on a plastic (which means flexible) cover afterall.

BTW guys I got it all back together and put new fuel injectors in, which ended up being the issue from the start. This truck has never ran this good/smooth.

 

[Mark_88]

Good to hear you got it fixed...

After having the head rebuilt I was turning the cam and noticed 4 distinct lopes (as in sorta bumps)...and also that they correspond to the valves closing on each cylinder...but when you line up the timing on the lope that is supposed to be tdc, it always seemed to be just a bit out...

Like you mentioned, the plastic markers are moveable, so I always just lined it up on the lope that was closest...and never had a problem setting timing marks that way...

 

[Duane867]

If you line the cam gear with out belt installed up a hair above the line during install and rotate it two full revolutions after the install it will line up perfectly every time. You rotate the crank two full revolutions to get the slack out of the belt via the tensioner and around the pulleys to tension it properly. You do not rotate the cam by its self. That does squat but get you out of time majorly.

 

[v8318cid]

That is more or less what I thought. Not sure where that notion came from... As to the timing marks, the cam mark on my truck isn't on the plastic from what I remember. Then again, the timing cover is gone anyway. Previous owner jacked it up and tried to fix it with some sort of glue, gorilla snot, or something. Just yanked it off and periodically check things to make sure nothing is too dirty to operate (crank sensor especially).
By the by, that tensioner is the world's biggest PITA (at least if you don't have the proper tool anyway).

 

[Mark_88]

gorilla snot

LOL~

I just went out and bought a new cover because I had no idea where the timing should have been...turned out I was exactly on...and didn't think to remove the vac line from the distributor to set the timing properly (as it says in the manual...I skipped that line...)