[56junkie]

Probably should be obvious once you know the difference,…. I don’t. I’m guessing this is long?
In my quest to simplify the PS and Alternator mounts on my Vortec 350, (previous thread), It’s been mentioned to be aware short/long water pump shaft. The car has Elect fan, so no issue there. How do I tell what I have?

 

[Greg's 56 Nomad]

If you are able to measure from your engine block to the front of the pump you should be able to tell.

Edit: I originally missed that this was on a vortec engine so I'm not really sure if this picture still works.

 

[Rick_L]

Three things.

First, this appears to be a factory serpentine belt drive setup. There are no factory serpentine setups for a "short" water pump. So it means you have a long one.

Second, there are different versions of a long water pump. One is the one for a conventional v-belt. That one has clockwise rotation when viewed from the front. Another is for the serpentine setup for non-Vortec engines. That would be engines from the 80s up through 1995. It is reverse rotation which is counterclockwise. Another yet is for Vortec engines 1996 and up. It is also reverse rotation. Don't confuse "reverse rotation" with "reverse coolling". "Reverse cooling" is something else entirely.

Third, a short water pump has no gap or almost no gap between the back of the water pump and the timing cover. A long water pump has a gap between the back of the pump and the timing cover of about 1/2", about the thickness of your finger. Judging from the photo, you may or may not be able to see this because that area looks pretty busy. The length measurement is useful if the pump is off the engine, because it's hard to measure with it on. Vortec pumps are slightly different in length.

 

[mr55/56]

Three things.

First, this appears to be a factory serpentine belt drive setup. There are no factory serpentine setups for a "short" water pump. So it means you have a long one.

Second, there are different versions of a long water pump. One is the one for a conventional v-belt. That one has clockwise rotation when viewed from the front. Another is for the serpentine setup for non-Vortec engines. That would be engines from the 80s up through 1995. It is reverse rotation which is counterclockwise. Another yet is for Vortec engines 1996 and up. It is also reverse rotation. Don't confuse "reverse rotation" with "reverse coolling". "Reverse cooling" is something else entirely.

Third, a short water pump has no gap or almost no gap between the back of the water pump and the timing cover. A long water pump has a gap between the back of the pump and the timing cover of about 1/2", about the thickness of your finger. Judging from the photo, you may or may not be able to see this because that area looks pretty busy. The length measurement is useful if the pump is off the engine, because it's hard to measure with it on. Vortec pumps are slightly different in length.

Rock Auto shows different part numbers for 87 350 Vbelt compared to 88 350 serp. belt for pickups

 

[56junkie]

Thanks for the good info here. Looks like I will need to get smart about the options. I had thought maybe just blow off the serpentine belt and go back to the old style, but that‘s probably stupid thinking. I really need to figure out what this engine is. I assume if I commit to disassembly and get down to read the block stamp, it will tell me correct?

 

[56junkie]

OK,…. Per R and M above, The gap is approx 1/2”, can just get the index finger in the the 1st knuckle! Then, with a steel rule laying at an angle, I can say the pump measures 7”, Block to pulley flange face. I have a LONG pump. Thanks!

 

[mr55/56]

I do not find wanting to ditch serpentine strange at all. I would do same as theydo not look right on old cars. The suffix code on pass side deck will tell you what rear motor iscfrom and what it was installed in.

 

[56junkie]

I do not find wanting to ditch serpentine strange at all. I would do same as theydo not look right on old cars. The suffix code on pass side deck will tell you what rear motor iscfrom and what it was installed in.

’Cause I really want to know…….. Can you tell me more? K1020XKA

 

[mr55/56]

K1020XKA does not come up at all. It is a LWP any idea of head casting numbers and dates. I never learned the symbols for late model heads.

 

[TheHotrodHandyman]

An SBC engine with the suffix "XKA" is a 99' model 5.7L out of a 1500 class vehicle (1/2 ton truck/van)