The 1947 - Present Chevrolet & GMC Truck Message Board Network

The 1947 - Present Chevrolet & GMC Truck Message Board Network (https://67-72chevytrucks.com/vboard/index.php)
-   Engine & Drivetrain (https://67-72chevytrucks.com/vboard/forumdisplay.php?f=24)
-   -   pulley ? (https://67-72chevytrucks.com/vboard/showthread.php?t=755966)

panhead59 01-30-2018 06:40 AM

pulley ?
 
I am replacing a 1981 chevy 350 engine with a 1989 350. I bought the 89 as a long block. So it has no harmonic balancer, water pump, fuel pump etc. I notice that the balancer for a 89 has a pulley that does not utilize the "v" type belt that the 81 engine uses. It uses the flat type belt with 3-4 grooves. (hope that makes sense). The balancers don't appear to be interchangable. There's a difference in the width of the two. So..... what's the easiest/least expensive way to get all the pulleys (thinking of the v groove power steering pump and alt.) the same? It doesn't look like I can just use the v groove pulley off the 81 on the new 89 balancer. I may be wrong, just asking. I haven't bought the new balancer for the 89 so it's hard to compare. :waah:

truckster 01-30-2018 03:49 PM

Re: pulley ?
 
In either case, the pulleys are bolted to the balancer, they're not part of the balancer. You should be running an 8 inch balancer (I"d get a new one) and you can bolt the pulley from the 81 on there if you're going to run the accessories from the 81.

The only difference that might exist is between the TDC locations on the two balancers - compare the keyway to the TDC location and buy the balancer for the engine you're using.

panhead59 01-30-2018 05:29 PM

Re: pulley ?
 
I know the pulleys are bolted to the balancer. OK so you are saying that there is basically no difference in balancers and everything should line up using the 81 pulley on the 89 engine. It'll be great if that's the case. I'll buy the new balancer and check it out. Thanks.

Captainfab 01-31-2018 12:12 AM

Re: pulley ?
 
Install a new balancer onto your '89 350 and all the accessories on the front of your '81 engine will bolt to the '89 350.

kwmech 01-31-2018 01:48 AM

Re: pulley ?
 
You will need a different flexplate as the 89 is a 1 piece rear seal and the 81 is a 2 piece. The bolt patterns are a little different

panhead59 01-31-2018 02:47 AM

Re: pulley ?
 
Yeah I noticed that. Got a new flywheel and pilot bearing. It called for a 12" clutch but my 11" bolted right up so I'm just gonna use it. Reusing 3 speed tranny on the tree
Tks for all the info !

Harold Holbrook 02-01-2018 05:22 AM

Re: pulley ?
 
I have a 1971 Blazer 350 with factory air does any one have pictures of the crank and water pump pulleys.

panhead59 02-11-2018 05:30 PM

Re: pulley ?
 
Update on pulley situation. Bought new balancer for 89 350 engine. It's a 8 in. Old balancer off 81 engine is 6 in. So ps pump bracket hit 8 in. Balancer. Got out cut off tool and modified stock bracket a little. I don't think it weakened it enough to matter. Pulleys line up- 1 down 2 to go. R an r water pump a couple times. 89 is longer towards radiator. Won t work. Used 1971 water pump. They r 2 in. Shorter. Pulleys now line up. 2 down. I have no idea how or where alternator bolts up. The brackets off 81 Don t line where I think they should. So my next ? Is r the threaded bolt holes on front of heads different depending on year , or r all 350 s the same ? Any pics of alt. Bolted up would be very helpful if anyone has one handy. So I m getting it....slowly. accessories r definitely not a direct swap. Thanks for any help and suggestions.

panhead59 02-12-2018 08:40 AM

Re: pulley ?
 
I guess I could always mount alt with those chrome universal mounts. Pretty cheap $25. Might have issues with headers though.

Captainfab 02-13-2018 01:02 AM

Re: pulley ?
 
Mixing a short water pump with long water pump pulleys and brackets, you will never get everything to line up right.

panhead59 02-13-2018 05:12 AM

Re: pulley ?
 
Absolutely. I am not mixing pulleys. You couldn't t if u wanted to- belts r different. Issue resolved see post 8

panhead59 02-13-2018 06:32 AM

Re: pulley ?
 
Another thing I learned is both 81 balencer
which is 6 in. And the 8 in. 89 balencer will accept the v belt 81 pulley. But water pump pulley bolt holes r different between a short (71) water pump and the longer 81 and 89. Ya learn something everyday around here !


All times are GMT -4. The time now is 08:59 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com