[QUOTE=christine_208;689865]Here's a pretty good guide on doing the LIMs. My experience was one of it taking a good amount of time to take everything off so I could get at the LIM gaskets.

How To Replace Intake Manifold Gaskets On A GMC Jimmy 4.3 Liter V6 To Fix A Coolant Leak - GM Truck Engine Repairs


2) Cut the heads off of four of the old LIM bolts and install them temporarily and use them as guide pins while lowering the LIM.

The easiest way to do this is buy a 1/4" wood dowel, and cut 4 separate 3" pieces to use as a guide in each corner, they drop in perfectly and allow you to slowly but perfectly drop the maniflold straight down in place.

 

I'd also give another side note to that manual. If You come to a part with a colored picture of a steering pump bolts hang hook - I found more convenient access from the top rather than underneath. Also, I'd take the distributor much earlier to get a better access to a studs on a backside.

Prepare to be patient I'm doing my LIMS and other things nearly two weeks now. Mainly due to the "other things".

 

Great advice. I can imagine cutting the heads off the old bolts using an angle grinder would just lead to missing fingers for me.

 

Update! I didn't tighten the distributor down enough, or something... I used the new seal in between the distributor and the block, and tightened it down tight - or so I thought. There's a substantial oil leak coming from that exact area, enough to where I don't want to drive it. Is it possible I need to tighten it down more? I don't want to break anything...

 

Bear n mind, the RTV should be "wet in touch" (according to GM 4.3 Vortec manual) while manifold gets in place, so You can't aim forever. I'd say apply the RTV, wait 5-7 mins and then lower the manifold under another 10 mins.

 

While replacing a distributor, I have found, that it somehow does not want to fuly "snap in" - it was sticking out by approx 1/4". On the other hand, in another (incorrect position of the rotor) it was snapping in easily, down to the bottom. I've tried turning the distributor cap side to side and it didn't want to go any lower. I have a few turns to the motor and it somehow snapped in... so I've tied the bolt.
In a Vortec manual You'd find all the torques for every single bolt & stud of Your engine. Highly recommend.

 

This is because there is a slot in your oil pump that the distributor shaft slides into. you must have got lucky because these 2 HAVE to be lined up right to get the rotor lined up right. Otherwise it wont run right or at all

 

Yup, I'm aware of that.

I just did not want to blur the picture. I've taken out the old spark plugs and brought 1st piston to a TDC (top dead center). Then I've put the distributor in the way, so the distributor rotor will match 6th cylinder. That actually is a good tip to remember, as the distributor rotor may change the position very easily when extracted.


Anyhow, I was unable to fully "snap in" the distributor. I've compared it with an old one and did not find a difference. But - like I said - I fit it in a way it was sticking out of a socket for a 1/4" and after giving a few turns to the engine, it went all the way down, so I tied the bolt with a torque specified in an engine service manual. Engine cranks & runs awesome, without any problems. Except I have to do some other things related to my cooling system, that I am speaking about in a parallel topic...
Cheers, Mike

 

After taking the cap and rotor back off so I could make sure it was aligned properly, I pulled the distributor out and examined the seal. Everything seemed to be good there, so I put it back, making sure the rotor was in the same place, and it dropped right in. Oil pressure is back up to around 40 psi on idle, so I know it's not leaking like it was. Thanks for all your help guys!

I'm going to start a new thread as I replace LIM gaskets, radiator&hoses, heater core, oil cooler lines, fuel injector assembly, and some smaller maintenance stuff like the thermostat, fuel filter, rear defrost, door hinge pins, etc. If I have the original water pump with 150k on it, should I replace that as preventative maintenance? A mechanic friend suggested that may be a good idea even though it isn't currently leaking at all

 

Replacement of my water pump as preventative maintenance is on my to-do list for when I do my next coolant system drain and flush. I want to keep my Blazer for several more years so I figure it is a good investment.

What I'm not looking forward to doing is trying to get the block drain plugs out. I tried last summer but could not get even the easier-to-get-to one on the driver's side to budge. I'll be starting my own thread to ask people how they got theirs out.