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87 GMC C70

jlittle2212

By jlittle2212
in Ask A GM Technician

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jlittle2212 Enthusiast

jlittle2212

Posted
Posted

This may be off topic to your forums, as I couldn't find a sub-forum for this. I apologize if I have posted in the wrong place. I am needing to know if the engine from a 84 GMC C70 will fit a 87 GMC C70. Looks as if the alternator is bolted up in a different spot and the power steering hardware isn't installed on the older one. Thanks to anyone who can help.

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Never worked on one of those big boys, but lots of times, the bolt-on accessories and mounts hanging off the front of the engine can be swapped from engine to engine ... and sometimes not - you'd have to look at the layout and see. If so you could just take the '84 mounts and accessories and bolt them on.

 

Whether or not the engine fits is a whole other story - I can't help you there. You could take some careful measurements of the motor mounts & overall engine dimensions and get an idea if it'll work or not, keeping in mind anything that will reduce clearance that's needed to run.

 

This is what I did with a little second gen.4.3 V6 to fit in a first gen S10 Blazer - there was no info on the net on if it would fit in there or not, so I had to measure it up and just go for it. Just visually, it looked to me like I could make it work anyway, as there wasn't alot of difference in engine blocks once you strip all the electronic & emission crap off. Lucky for me, it fit with just some minor shimming of the second gen motor mounts. The accessory mounts also fit, although the threads were all metric on the second gen, and some holes that were never used had to be cleaned out with a tap, and used.

 

If your determined enough, you can make anything work. :cheers:

grampadirt Senior Enthusiast

grampadirt

Posted
Posted

Those are both big block engines,I'm betting they'll swap :thumbs:

 

Question though...is the '87 a TBI intake?

jlittle2212 Enthusiast

jlittle2212

Posted
  • Author
Posted

Those are both big block engines,I'm betting they'll swap :thumbs:

 

Question though...is the '87 a TBI intake?

Give me some insight on the TBI intake? The only thing I see visual is the alternator is bolted in a different spot on the 84 engine. I can swap all that over from my other engine, however. I could also switch the intake, right? Consider me a noob on these Chevy's! lol :dunno:

grampadirt Senior Enthusiast

grampadirt

Posted
Posted

I would guess you can switch the intakes UNLESS the '87 is a TBI.In '87 GM went to TBI in their pickups and eliminated carbs.So the question is,are both of yours carb'd engines? Can you post pics of both?Here's a pic of my 454 TBI.

 

DSC01972.jpg

 

Actually now that I think about it I see no reason why the '84 intake and acc. wouldn't fit the '87 engine.

 

I apologize,I just went back and looked at a previous post,you said they were both carb'd,do the swap :thumbs:

 

One more thought...have you checked the '84 to make sure it's worth the effort? I'd at least do a compression check.

jlittle2212 Enthusiast

jlittle2212

Posted
  • Author
Posted

Actually now that I think about it I see no reason why the '84 intake and acc. wouldn't fit the '87 engine.

 

I apologize,I just went back and looked at a previous post,you said they were both carb'd,do the swap :thumbs:

 

One more thought...have you checked the '84 to make sure it's worth the effort? I'd at least do a compression check.

 

I currently own the 87 model which has spun a bearing and locked up. This engine was "running when removed" with a fifteen day warranty. I get to keep my old engine and the price ($500) is way beyond the cheapest I have found. Almost half price. The 87 had 150,*** miles and a TON of idle hours and oil leaks. I was waiting on this to happen so I could swap. The 84 comes with everything from fan to flywheel minus the carb. starter and alternator as well. I am just taking a chance... Hopefully, it turns out well!

 

Thanks for all your help! :fingersx:

jlittle2212 Enthusiast

jlittle2212

Posted
  • Author
Posted

I will try to update you. I am supposed to have the engine by Monday. This is the 84. See anything I may be missing? Everything seems to be pretty clean and in tact.

 

$(KGrHqN,!mEFIG!DCc,gBSCu)B!Qmg~~60_57.J

Jsdirt Senior Enthusiast

Jsdirt

Posted
Posted

Nice - I was expecting to see a diesel.

 

Wish every vehicle was still that simple. Everything you need, and nothing you don't. :cheers:

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