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-   -   Belt size a little too long (https://67-72chevytrucks.com/vboard/showthread.php?t=729685)

dmw319 02-07-2017 10:12 AM

Belt size a little too long
 
My engine has been squeaking a little on idle and I've narrowed it down to what I think to be a loose belt. I am using the standard size belt. It's the bottom one, the smaller of the two that goes to the crank and power steering pulley. For some reason, I have it all the way as tight as the power steering tensioner will allow and it is just not snug enough and I think that's why one of the pulleys is squeaking. Is there another belt that is the right specs but just a tad bit shorter that I could use? Anyone else run into this issue?

Thanks!

Wrenchbender Ret 02-07-2017 12:23 PM

Re: Belt size a little too long
 
Take the belt to the local parts store. They can measure it or get the length from the part number. Get one about 1 in. shorter. A little bit goes a long way.

dmw319 02-07-2017 12:29 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by Wrenchbender Ret (Post 7851186)
Take the belt to the local parts store. They can measure it or get the length from the part number. Get one about 1 in. shorter. A little bit goes a long way.

this was the method I was going to do, just wondering if anyone else had a similar thing happen

1968aj 02-07-2017 12:48 PM

Re: Belt size a little too long
 
if the belt is real close to fitting an inch longer will be too big. I would find one that is about thickness of the belt longer. I just made several trips to parts store to get one to fit. a little bit makes a big difference.

dmw319 02-07-2017 12:49 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by 1968aj (Post 7851225)
if the belt is real close to fitting an inch longer will be too big. I would find one that is about thickness of the belt longer. I just made several trips to parts store to get one to fit. a little bit makes a big difference.

I see your point. In this case though, the belt is too big. I need a slightly shorter belt.

jsera 02-07-2017 01:16 PM

Re: Belt size a little too long
 
one inch is a lot it this belt already fits, belts are usually measured by the manufacturer in mm... what brand belt and what setup (serpentine, v-belt?)

dmw319 02-07-2017 01:28 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by jsera (Post 7851259)
one inch is a lot it this belt already fits, belts are usually measured by the manufacturer in mm... what brand belt and what setup (serpentine, v-belt?)

It's a Gates 7350 belt.

paul blair 02-07-2017 09:11 PM

Re: Belt size a little too long
 
Consider the width of your power steering belt, if it is to narrow it will be too deep in the v grove. Wider belt will have more bite in the pulley v grove! My original p/s belt fills the pulley flush or a little more to the top of the pulley! NO SQUEEK SINCE 1969--36,000mi. hope this helps! HAPPY TRAILS

special-K 02-07-2017 09:56 PM

Re: Belt size a little too long
 
Go down a 1/2". Your belt is a 7350, get a 7345. At lest that's how I understand the belt numbers work...unless they changed to metric. The last three digits are inches and fraction... 450 = 45.0" and 455 = 45.5". That's always worked for me

hjewell2 02-07-2017 10:32 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by special-K (Post 7851715)
Go down a 1/2". Your belt is a 7350, get a 7345. At lest that's how I understand the belt numbers work...unless they changed to metric. The last three digits are inches and fraction... 450 = 45.0" and 455 = 45.5". That's always worked for me

That is correct right to a T

dmw319 03-06-2017 04:19 PM

Re: Belt size a little too long
 
Thanks yall.

They didn't have any 7345s in stock, but they did have 7340. It was a little short, but I was able to get it on there with the assistance of a flathead screwdriver. Got it tightened down and no more belt squeal!

El Dorado Jim 03-06-2017 07:37 PM

Re: Belt size a little too long
 
now keep the new belt package in the glovebox so you will know next time what belt to get.

GerhardH 11-23-2019 01:27 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by special-K (Post 7851715)
Go down a 1/2". Your belt is a 7350, get a 7345. At lest that's how I understand the belt numbers work...unless they changed to metric. The last three digits are inches and fraction... 450 = 45.0" and 455 = 45.5". That's always worked for me

I had the same issue, thank for your excellent advice
http://67-72chevytrucks.com/vboard/s...42#post8631742

Killer Bee 11-23-2019 01:58 PM

Re: Belt size a little too long
 
the belt sizing above is correct, thanks Tim..

since the adjustment travel is only half of the belt's circumference, there should be plenty of sizes to choose from..

but the bigger question I have is why the stock size belt wouldn't fit assuming the factory brackets and pulleys are in place..

have you loosened all pivot bolts and adjustment bolts completely and checked for full range of motion?

engine size and year not disclosed and I'm not sure for which engines and when brackets changed, but I would verify that first..

there has to be a reason the correct spec belt that fits a million trucks doesn't fit yours..

good luck!

GerhardH 11-23-2019 02:11 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by Killer Bee (Post 8631760)
the belt sizing above is correct, thanks Tim..

since the adjustment travel is only half of the belt's circumference, there should be plenty of sizes to choose from..

but the bigger question I have is why the stock size belt wouldn't fit assuming the factory brackets and pulleys are in place..
you are right, interesting question
have you loosened all pivot bolts and adjustment bolts completely and checked for full range of motion?
Yes, the pump is on the end of adjustment travel
engine size and year not disclosed and I'm not sure for which engines and when brackets changed, but I would verify that first.
1968 327 guessing everything is original

there has to be a reason the correct spec belt that fits a million trucks doesn't fit yours..
Found to change the belt size was an easier way, but you are right, Interesting, will investigate. Would like to know dimensions from pump pulley and crankshaft pulley
good luck!


Let's investigate

racerop 11-25-2019 07:50 AM

Re: Belt size a little too long
 
I would entertain that the
power steering pump was
changed at least once and a smaller pulley
was on that pump already and didn’t
get changed to the original size

Steeveedee 11-25-2019 12:08 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by racerop (Post 8632636)
I would entertain that the
power steering pump was
changed at least once and a smaller pulley
was on that pump already and didn’t
get changed to the original size

Now, there's a thought! After all these years, who knows what could have been done? When I think back on all the things I did, that wouldn't be a surprise.

geezer#99 11-25-2019 01:03 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by racerop (Post 8632636)
I would entertain that the
power steering pump was
changed at least once and a smaller pulley
was on that pump already and didn’t
get changed to the original size

Or the pulley was the same size but a wider groove.
Belt would sit lower in the groove and not make contact with the groove sides.
Belts are supposed to sit level with the edge of the pulley.
Check the width of the belt too.

GerhardH 12-01-2019 07:15 PM

Re: Belt size a little too long
 
5 Attachment(s)
Dear fellows, thanks for your posts and your opinion highly appreciated.
Some investigation done:

1. Remember 1968 327 with PS (Power Steering), AC (Air Condition)

2. Assuming that the original belt routing as as follows (see picture 1):
Drive shaft 3 groove to Power Steering 1 groove
Drive shaft 3 groove to water pump/fan 2 groove to generator 1 groove
Drive shaft 3 groove to water pump/fan 2 groove to Air condition 1 groove

3. Assuming that the original parts are mounted:
379194361 Steering pump pulley (picture 2)
3923898 Drive shaft pulley (picture down below)
3924557 Steering pump support (picture 3)

GerhardH 12-01-2019 07:36 PM

Re: Belt size a little too long
 
5 Attachment(s)
The pump was changed in 2018
First picture pump before 2018 installed, Banjo Style Power Steering Pump, second picture now installed, different form.

GerhardH 12-01-2019 07:43 PM

Re: Belt size a little too long
 
3 Attachment(s)
If it comes to the belt 7350 the length is 35.57" this is a little bit longer than the original one 35".

The original with is 3/8" (0.375") , the 7350 has 13/32 (0.41"), but in my opinion the belt has a good setting in the groove.

The only explanation I have is that the pump himself with the newer design has not exactly the same geometry and together with the slightly longer belt it comes to the difficulties.

Will ask the workshop guys which pump they have installed, I was in this time under time pressure and have not followed the process deeply.

Anyway it was great fun to investigate all the part numbers and learn about my truck from all of you.

Sheepdip 12-01-2019 08:11 PM

Re: Belt size a little too long
 
Quote:

Originally Posted by El Dorado Jim (Post 7878297)
now keep the new belt package in the glovebox so you will know next time what belt to get.

That's "Old School" El Dorado :lol::lol:
My grandkidz showed me how to become high/modern tech with my iPhone and the "Notes" app, I've got a section for each vehicle with pertinent info for belts, hoses, brakes, bearings, filters etc., etc.

Even got one for my forklift!.....You are Welcome! :gmc2::gmc2::metal:

GerhardH 12-02-2019 10:20 AM

Re: Belt size a little too long
 
Today I found out that the banjo style and the teardrop style have the same dimensions regarding holes and bolts. Its just a different reservoir style.

https://www.tuffstuffperformance.com...tructions.html

No idea why the 7530 belt is to long.


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