Engine swap diary

[jaredts]

If I understand right, the distributor that you have for the 4.3 is ESC equipped.  You can get a new HEI distributor on ebay for under $50 shipped for a 4.3.  Then it would be a typical one wire hookup.  If your springs and weights are rusty and worn it would be a good investment anyway.

[Stewart G Griffin]

Mmmmm......i'm kinda queezy on those ebay distributors.  i think msd and a few others make one for a 4.3.  Not sure if GM still carries one.  i'll be rebuilding mine eventually.  For now i connected the green and black wires on the plug to the ESC module.  Should function like a regular HEI now.

[Stewart G Griffin]

Removed all the bellhousing to block bolts.

Tried to remove the converter to flexplate bolts but there's a problem;  The engine has seized due to the overheating so i can't get to the two other bolts.  The converter will have to come out with the engine.  Then, i will have to completely disassemble the engine---how else can i get to the converter bolts?

undid the starter wires and brace.



Got it cleaned up as far as a lot of the emissions stuff and A.I.R. tubes.  The oil fill tube is a nice touch but i think i will just use a cap.

i'm not sure if you can notice, but the carb is higher than the top of the distributor so might be able to use the v-8 air cleaner housing.  i forgot to take the v-6 air cleaner housing when i bought the engine and when i realized it two weeks later he said he threw it out.   

As i was saying this carb on the engine now is original to the truck.  The carb that came with the engine was totally wrong for the application (was a generic rebuilt unit) and even had a heat riser style choke and i'm pretty sure these trucks with the 4.3 never had that style choke.

[Irish_Alley]

you can pull the trans back and leave the tc attached to the flex plate. it will be a tad more messy but at least you can get them apart

[Stewart G Griffin]

But can't i just pull the engine and the converter will come with it?   BTW, don't think i can do it today because of rain.

[Irish_Alley]

If you have enough room I don't see why not but you then have to clear the trans so this means pulling the motor forward enough and straight to clear the trans and the oil pan on the cross member. I think the cross member will be the hardest part

[Stewart G Griffin]

Pulled engine(305) today and was able to slide the converter off with the engine.  But there's a problem;  Before the engine came out, i was able to get a small space between the engine and trans bellhousing.  i thought i could slip a wrench in between the flexplate and engine and get the last converter bolt out.   i seemed to have rounded it off.  So now i definitely have to disassemble the 305.  Take the crank out and i'll probably have to cut the last converter bolt?

Got all the main bearings off and #2 didn't look so good. 

[Jason S]

If you get the crank/flexplate/convertor assembly out, there may still be enough shoulder to get a six point socket on the bolt.

[Stewart G Griffin]

If you get the crank/flexplate/convertor assembly out, there may still be enough shoulder to get a six point socket on the bolt.

Hopefully.  i actually tried to use a 15mm flare wrench(bad idea?) as it worked on the other bolt that was exposed (near the oil filter) and had to use it in that position because the six point socket wouldn't fit.

[Stewart G Griffin]

Unfortunately, due to work scheduling and other stuff that has cropped up i can't work on the truck probably until the weekends.

[Stewart G Griffin]

Was finally able to separate the converter from the flexplate:

Friday night i went over to a friend's workplace after i got off from work myself.  i debated whether to go because i was tired, had a long week, and just wanted to go home, but for some reason i decided to pop over there for a few mins.  We had a little conversation about my dilemma and he thought that taking the engine completely apart to take the crank out was too much work and suggested i try getting to the converter bolt with a different type of wrench.  (he used to work as a mechanic). 

i'm sure glad i went over there and had that little conversation because it got me thinking and doing some more research:

If you can get two of the converter bolts off, then there's juuuuussst enough space to fit a narrow 11/16" wrench in there to undo the flexplate to crank bolts:


Now, as you might know, there IS enough space between the back of the engine block and the flexplate to fit a 15mm wrench to get to the converter to flexplate bolt.  But since it was rounded off, i didn't want to take any chances;  i figured i would get the flexplate off completely and then i would have clear access to that bolt and could deal with it better out in the open.

The flexplate came off rather easily considering it's been on the engine 36-7 years.   i've dealt with much more stubborn flexplates on newer engines.

Once the flexplate was off i was able to put a 6point 15mm socket on the converter bolt and it grabbed it well enough so i could loosen it.  It turns out the bolt was not rounded off THAT bad, but i'm still going to use a new one in place of it.



What did i learn?

1) If you get yourself into this situation---where the engine is seized, you CAN get to the converter bolts.  But you need the right tool------a very narrow and long 15mm box wrench.  AND there can't be ANY offset.  It has to be flat.  It won't work if the wrench has any offset.

2) You need the right tool to do the job.  i used a 15mm flare nut wrench---because it was the only i could find that would fit.   Had i spent $10 to get the right tool i could have saved a lot of trouble.......   i don't think these flare wrenches are designed to take a lot of torque.  So what may have happened is that the jaws opened up enough to round the bolt head off.

[Stewart G Griffin]

It's probably more organized if i put everything here:





1) In initially comparing the different perches/towers  between the 6 and 8 i was worried that the crossmembers for v-6 and v-8 trucks were different.  As it turns out the crossmembers are the same.  And the rearmost holes in the crossmembers DO match for both v-8 and v-6 perches. (holes closest to cab, farthest from front bumper)   However, being my truck is an 83  (and the v-6 was not offered until 85) i do not have any matching holes on the framerail for the v-6 perch.   So i will have to drill three holes in the frame on each side.   i also need to move the engine over about 1/4 an inch to center it up better.

Any tips for drilling into the framerail?

2) My brother came over to visit and commented that the engine looked really small in there.  (It does look kinda small in there.)   And was concerned whether it would be able to move the truck?    (he's not a truck guy)   i assured him that these trucks came with this engine standard and pickup trucks in general have 6 cylinders as the standard engine.  LOL

3) In trying to better center the engine in the chassis---from left to right----i felt it need to go about 1/4" inch to the right i discovered that the transmission mount is shot.    It's a TH-350C

So, i will have to take care of that before i can do any drilling into the frame to secure the new v-6 perches.

[Greybeard]

Any tips for drilling into the framerail?

Two- lots and lots of lube and use a split point that is very sharp (new), (buy a couple)

OK I lied, more than two; use a slow speed and heavy steady pressure, do not let the drill rock any at all. If it smokes, change bits, you just ruined the one you were using. Chips should come out as a long curl not small chunks. If they come out as chunks you aren't pressing hard enough OR the speed is overrunning the bits cutting ability. A frame is not really all that hard of steel, it should drill rather easy.

[Stewart G Griffin]

What is a split point?

i can't do any drilling yet because i discovered my rear transmission mount is totally shot and will need to be replaced.  It's separated into two pieces.  And i think this was causing difficulty getting the engine centered in the frame----needed to go over to the right about 1/4 inch.

i'm thinking of going with polyurethane.

[zieg85]

Here is the line up for reference.  The back pair of hole (green arrows) are the V-6 mounting holes where the (orange arrows) should be for the V-8