71 GMC engine swap-arino

[Kalums]

Well guys this is going to probably be a lengthy thread but I'd rather start one and ask a bunch of different questions than 80 different threads. So here goes... :
I'm going to swap the motor out on my 71 GMC K2500 the engine that is currently in there has "issues" with cylinders 7 & 8. I pulled the valve covers and intake manifold. I have found bent push rods and stuck or bent valves also one broken exhaust valve spring (multiple pieces) I'm pretty sure I could probably get away with replacing heads, but I have an "L44" GM crate motor that I was looking to sell but didn't (I didn't think 1500 was too much for a crate motor, but apparently ppl in Phoenix do *shrugs*) this crate motor is a "1993 spec". GM part # 12681430 (discontinued/ superseded.) This engine was bought in 2017 and sat in it's crate in the plastic in a garage, until I got the truck in July. This crate motor has the spot for a mechanical fuel pump, but no hole to the cam and from what I've read probably doesn't have a pump lobe on the cam( but it is still a maybe).
Question 1) What fuel pump should I use as my truck doesn't have an EEC fuel tank and no way (that I'm aware of) for a "return line" from any pump? I was looking at the Carter #4594 or Facet solid state pump #40345 or #40109
2) Should I swap to a serpentine system or try and find new to me "correct" belt pullies?
3)What do I need to do to this engine before I swap it in ie check valvetrain lash, a marvel mystery oil "soak", etc.
4) Should I pull these rear oil galley plugs and "tap" them?
5) This doesn't appear to have the vertical center intake bolt holes, my Weiand Action Plus (8004) seems to sit flush. Fel-pro gasket #1205s-3 and send it?
For all of you guys that have done this before these may seem like silly questions but I've never swapped an engine before and most of the internet is such a pit of opinions built on lies and speculation that I'm more confused now than when I started.

[Kalums]

More pictures

[MARKDTN]

That is the later centerbolt heads so the center 2 intake holes are not at the same angle. You can "hog out" the holes in the intake and use wedge shims on those bolts or get a different intake.

Why can't you use the pulleys from your current engine? Serpentine is nice, but not necessary (and IMHO stay away from CS130 alternators).

Without taking it apart you will have to use an electric fuel pump.

I don't think I would do anything special other than prime well with a drill and rotate the crank a couple times while doing it. It looks pretty clean to me.

I would not do anything with plugs?

Also, this is not a roller cam engine. Be sure to use a high zinc oil and follow the break in process to the letter.

[Kalums]

Originally Posted by MARKDTN

That is the later centerbolt heads so the center 2 intake holes are not at the same angle. You can "hog out" the holes in the intake and use wedge shims on those bolts or get a different intake.

Why can't you use the pulleys from your current engine? Serpentine is nice, but not necessary (and IMHO stay away from CS130 alternators).

Without taking it apart you will have to use an electric fuel pump.

I don't think I would do anything special other than prime well with a drill and rotate the crank a couple times while doing it. It looks pretty clean to me.

I would not do anything with plugs?

Also, this is not a roller cam engine. Be sure to use a high zinc oil and follow the break in process to the letter.

Staying away from the CS series alternators, gonna try and stick with the 12si I(94 amp) just got.
Now that you mention it I see that those center holes threads are at a different angle... Any idea where to get those shims/washers? I'd rather not hog out the holes in the intake if I don't have to.
I'm going eventually add A/C so I was trying to plan ahead and get a long nose water pump which means my current pullies will be un-usable.
I was also planning on using the Amsoil "break-in" high zinc oil, How do I prime it with a drill? Again newbie here. Thank you for the reply and help.

[cj847]

Priming tool

https://www.amazon.com/Htostar-Racin...35b9659f0fc071

[Kalums]

Originally Posted by cj847

Priming tool

https://www.amazon.com/Htostar-Racin...35b9659f0fc071

You rock I didn't know that even existed. 👍

[MARKDTN]

Originally Posted by Kalums

Staying away from the CS series alternators, gonna try and stick with the 12si I(94 amp) just got.
Now that you mention it I see that those center holes threads are at a different angle... Any idea where to get those shims/washers? I'd rather not hog out the holes in the intake if I don't have to.
I'm going eventually add A/C so I was trying to plan ahead and get a long nose water pump which means my current pullies will be un-usable.
I was also planning on using the Amsoil "break-in" high zinc oil, How do I prime it with a drill? Again newbie here. Thank you for the reply and help.

Intake bolt wedges
https://www.holley.com/products/disc...ct/parts/90748
These are discontinued but you can make something similar. I think you will have to at least enlarge the holes in the intake to make them work.

You can get A/C on a 67-72 so no need to go long pump for that. I would not use an A6 compressor, but there are kits to put a Sanden on which will have the brackets you need anyway. And if you do go serpentine, get one without an R4 compressor like a Corvette with Nippendenso or the later 4.3 or 5.7 with the silver compressor and then get a Nippendenso to replace it (not an offshore). With any of these you will need a different alternator and I would want a CS144 not a CS130.
https://www.classicindustries.com/pr...Gmph3crLtlBrGx


To prime the engine you need a priming tool or an old cut off distributor. It's possible to just use a screwdriver with no handle, but I would want the whole thing so it will oil the top end since this engine has been sitting and with all the problems with breaking in flat tappet cams. Some are just shafts that don't close a gap to oil the top end.
https://www.summitracing.com/parts/p...gaAgQnEALw_wcB