1987 Chevrolet 350 tbi high idle

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AuroraGirl

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1978, 1980
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K10, K25
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400(?), 350
So I should focus more on odd numbers and not just settle for a 6? The only bad things I saw in the reviews for the 6 blade was wind noise one person compared it to a supercharger. One said jet engine. So I mean if I moves air no biggy, my truck is by no means quiet but it’s not obnoxiously loud. A little fan noise won’t bother me
I mean its prob more the design of the individual fan than the blade count to contribute. but just get yourself an old OE one on ebay which came in 3 5 7 9 i do believe
 

iamtherealJayy

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1987, 1978, 1976
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V20, K10, K10
Engine Size
350, 350, 350
Take 3 out of the equation, if I’ve got a 3 now why bother looking at 3 blade fans. I may have an old 350 fan somewhere I can try and take off something else(family did dirt track racing so I have several Chevy parts laying around) and put it on the truck if I can just use an old one. For the water pump I figure get new studs for it since they’re like $5 more and they’re new? I dunno saw it in the tutorial for changing it. I’m trying to stay within a budget but I’m willing to spend what I have to to get my truck back if I know that’s what it needs.
 

AuroraGirl

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yes new studs the right length ones
 

yepyep

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v20
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350 tbi
what was the solution to the high idle? my parts square did this never could figure it out
 

gmbellew

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what was the solution to the high idle? my parts square did this never could figure it out
in this case it appears to have been a vac leak through the throttle body gasket and maybe also a gunked up and worn out IAC.
 

iamtherealJayy

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@yepyep exactly what @gmbellew said, my throttle body gasket was original… I asked dad if when he swapped the intake manifold to the new block if he replaced anything and he said he never removed the throttle body. And once I got that replaced it idles too low now, I got a timing light today(had him go to the semi trailer parts building while I was at work) and I also got two 7 blade fans @AuroraGirl but one has a spacer? Is a spacer better or worse? Anyways I need to get my timing set to 0° and replace my IAC so my idle kicks up to around 750 instead of 650. Then hopefully I’ll have my truck back
 

AuroraGirl

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@yepyep exactly what @gmbellew said, my throttle body gasket was original… I asked dad if when he swapped the intake manifold to the new block if he replaced anything and he said he never removed the throttle body. And once I got that replaced it idles too low now, I got a timing light today(had him go to the semi trailer parts building while I was at work) and I also got two 7 blade fans @AuroraGirl but one has a spacer? Is a spacer better or worse? Anyways I need to get my timing set to 0° and replace my IAC so my idle kicks up to around 750 instead of 650. Then hopefully I’ll have my truck back
ONE WIth a spacer is intended most likely if 1) you dont use a clutch 2) you need to make up a distance between shroud rad etc like a v6 would prob need a spacer vs a v8 etc
 

iamtherealJayy

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350, 350, 350
So I need to remove the spacer since I’ve got a fan clutch? That’s what I figured since it seems with a spacer it would be too far in the shroud. Should I go ahead and order a water pump? Or start with the fan and timing and see what the temperature does? And I can’t find an infrared thermometer locally anywhere so if I order a water pump I’ll order an ir thermometer as well.
 

AuroraGirl

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So I need to remove the spacer since I’ve got a fan clutch? That’s what I figured since it seems with a spacer it would be too far in the shroud. Should I go ahead and order a water pump? Or start with the fan and timing and see what the temperature does? And I can’t find an infrared thermometer locally anywhere so if I order a water pump I’ll order an ir thermometer as well.
harbor freight.

a water pump should be kept locally.

Lower tier brand but you can fix that later, in my opinion, just get a new one on. AT LEAST, pull yours off and check it. if you really think its good after that, put it back on. easy as pie to remove
 

iamtherealJayy

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350, 350, 350
I’ve got a harbor freight about a half hour away I can check there. So I should stick to oreillys water pump? What about fan clutch? Should I replace it? Local? Or order one? I’ve obtained two different 7 blade fans so the fan is covered.
 

AuroraGirl

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I’ve got a harbor freight about a half hour away I can check there. So I should stick to oreillys water pump? What about fan clutch? Should I replace it? Local? Or order one? I’ve obtained two different 7 blade fans so the fan is covered.
You should try and get a fan clutch but you have a spacer. See where the fan fits with that on the water pump, it it’s in the right spot you can skip for now and just order it in. If not I would get it local to. Just either buy stuff with warranty if you can that’s decent or at least Google ahead if they are any good whatsoever
 

iamtherealJayy

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Like the one person said previously about the different heat ranges and regular duty/heavy duty, what fan clutch should I be looking into? An oe replacement? Or a better one? Do I need the fan clutch or can I just use the spacer? I assume I’d lose some horseys if I just used the spacer correct?
Oreillys has a couple fan clutches one is like 7.42” diameter and one is 6.something. All other numbers are the same when comparing them.
 

iamtherealJayy

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Well after today’s shitshow… I’ve got a new water pump I’m putting on tomorrow and also a new lower radiator hose since it felt too soft in my opinion where it connects to water pump. Also got a timing light. Do not have a fan yet unless I run without a clutch since my 3 blade fan the clutch is on outside of fan(not between fan and engine) and the bolts on the spacer don’t thread with the water pump. Did get new studs for water pump. So may just use the factory 3 blade and hope it was a mix of lower radiator hose and water pump. Although the lower hose isn’t very old… not even two years old. Next post is some pictures from today
 

iamtherealJayy

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Engine Size
350, 350, 350
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There were no gaskets for the water pump but instead some reddish orange? Gasket maker? So I assume it’s the original water pump since block was replaced and water pump wasn’t so they used gasket maker instead of getting new gaskets.
 

85Sierra Classy

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There were no gaskets for the water pump but instead some reddish orange? Gasket maker? So I assume it’s the original water pump since block was replaced and water pump wasn’t so they used gasket maker instead of getting new gaskets.
In looking at your picture, the water pump gaskets are still hanging on the engine block. They’re just the thin paper type gasket. Hopefully you scraped them off before installing the new pump and gaskets…
Old water pump looks nasty though.
 

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