Timing adjustment on MPI engines???

ezwrangler

New member
OK, I have finished putting in the reman engine in my 1994 YJ (thanks for those of you who have answered my questions along the way - it really has been helpful!!!). I have primed the engine with oil (drill and a long screwdriver), cylinder number one is set a TDC, the distributor is installed and I should be ready to go. Reading the Haynes (and several posts) it is emphasized that the timing needs to be set/adjsted as soon as possible after firing it up - but it footnotes that this is for carb engines only (mine is the 4.0L fuel injected). So, my question is, do I need to worry about anything with this engine? Is there any adjustement I need to make after firing it up? Does the computer do all this for you? There is no discussion about adjusting timing on the MPI engines in the Haynes as far as I can tell. After all the time, energy and $'s I've put into this thing, I dont want to blow it right at the end...

Also, I put in 10W30 as the manual suggests, but some posts suggest that there is not enough zinc(?) in the newer run-of-the-mill oils to successfully break in a reman engine??? Some suggest using a high quality diesel oil 15W40 like Rotella etc. Anyone have any opinions on this? Should I drain the 10W30 out and put in the heavier oil during breakin?

thanks for any insight here... :?|
 

OK, not much help here, I'm sure.....but back in the day when we used to set/adjust timing all the time, there was a bolt at the bottom of the distributor that you would loosen and then twist the distributor this way or that.................my '03 doesn't even have a distributor..............there HAS to be something of that nature if you are going to manually adjust the timing. You got anything like that??

As far as the oil goes.........my useless opinion only........I think you'll be fine. Just change it out after 500 or so miles and if it's still bothering you, change it out after 500 more. If it's a bad build, all the zinc in the world isn't going to help. If it's a quality build, good clean oil changed often should suffice.

my $.02
 
Thanks again MUD4FEET.

Yeah, I do have a bolt and clamp at the base of the distributor, but you cannot turn it (the distributor) because it is designed to lock into a specific position (there is a guide-hole on the flange of the distributor that the clamping screw fits into - you simply cannot turn the distributor...). Weird, but thats the way it was designed i guess. It still seems like you should be able to adjust the timing though. My 88 has just what you described, and i can turn that distributor just as one would expect (and as the manual describes).

Anyway, I guess ill just go for it and hope for the best... :)

Thanks
 
on the 4.0L the dist either is on or off a tooth either way. the ecu controls all the fine tuning. as far as oil goes you can just get a good full synthetic for the break in but you really should dump it @ 500 miles. so kinda seems like a waste of $$. kinda your choice,
 

YJDAVE,

Great thanks, that was what I was hoping to hear. I am positive I got the ditributor lined up properly for cyl #1 TDC, so now that I know I dont need to worry about running around trying to adjust the timing right after startup, while making sure the oil pressure is up, I feel much better.

thanks too for the tip on the oil!
 
Timing is not adjustible on the MPFI engines.

There are ways to tinker with timing if you're like me and mess with mods on the engine. But you should be fine.

I'd break in the engine with good 'ol 10w30, don't worry about synthetic until later on.
 
Cool, thanks BOUNTY_HUNTER.

All you guys are great!

I appreciate the help. I'll let you know how it all goes. I should be able to get to it this evening...
:-)
 
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