Reddeath210

iTrader: (1)

So i have an 86 trans am with a 383 stroker kit with a holly street avenger carb. She runs great, needs to be tuned a little bit, but that's really it. Now what i have noticed is if i drive her more than around 20 minutes, my gauge tells me shes running at around 250 degrees (f)

Now i don't know if my gauges are off because i know my speedo is from my rear but that shouldn't effect my temp gauge. I was just wondering if there's some aftermarket cooling devices i should consider to make her run cooler, and if i should run a new temp gauge. I am still learning when it comes to engine work, so any tips or tricks would be greatly appericated

Reddeath210

iTrader: (1)

Bump

NotsosleepyZ

make sure your fan is ruinning, coolant is flushed thoroughly, you can get the additive from any parts store then run lots of water till its clean, check your thermostat mak sure it is not frozen shut, (new one is like 20 dollars) then if the fans are working the thermostat is replaced and the radiator flushed (and pressure wash the outside to get debris off the fins of the radiator) maybe check into a new water pump cause 250 is waaay too hot

Steve86TA

iTrader: (57)

You need to make sure the air dam is intact under the front nose. These are very important to cooling in these cars. Should be a piece of black plastic, probably 6 inches tall or so mounted under the radiator support

Reddeath210

iTrader: (1)

@steve its gone, any place i could get one?

and @notso we where thinking it might be the water pump, since everything on the engine looks new but the pump. Suggest any brand for water pumps?

1gary

Any coolant loss??. Constant bubbles in the rad after the stat opens??.

Reddeath210

iTrader: (1)

@gary i havent heard any bubbles, i seems to be idling at a steady 180, but when i get it on the road and give it alil bit of juice she shoots up to around 220. On long trips as high as 250

1gary

Not what you heard,but what you see at the rad neck once the stat opens.

Reddeath210

iTrader: (1)

@Gary I havent took the stat off yet, after a drive. Should I to look for bubbles

Mike's 87

No!! Remove cap then let motor idle and warm up from cold. Never pull cap after hot!! You may need a lower temp thermostat. And a toggle switch linked into fans to manually turn on. I have a 383 stroker with 10.25:1 compression a low temp thermostat and new water pump and still have air dam... I still overheat in town. Not usually on highway. Maybe try additive that "guarantee's" to drop temp 40° just something I've considered. I am told we get hot due to cylinder walls being thinner by being punched out. Thinner wall = more heat transfer to water jacket.

Reddeath210

iTrader: (1)

@mike, i read that aswell, that the 383's can get alil bit warmer then usually because of the thinner walls. The guy before me just put a thermostat in, but i dont know if it was low temp or not. My fan is on all the time, i dont think it has a switch built in, i think it just starts up as soon as the car does. Sadly i dont have a air dam period
For water pumps is there a good brand i should consider when getting one, or a specific type that would cool it better.

What would you say your 383 runs at temp wise idling, and driving around in town?

Mike's 87

I have dual electric fans that leave both on otherwise I overheat in no time10-15 min will be in red at idle

Reddeath210

iTrader: (1)

I have a single electric fan, how would i go about putting 2 on it

sofakingdom

iTrader: (1)

If it gets warmer on the highway than going slow:

1. Air dam - this is where I'd suggest you start

2. Not enough timing advance at high speeds; either no centrifugal (e.g. computer-controlled dist without a computer), or no vacuum advance (same as above, or line disconnected)

3. WAY WAY WAY lean.


Leave the thermostat alone. It's not the problem, so messing with it won't produce a solution. All you'll do is create a further problem you'll have to go back and fix later. Life is too short to set minefields like that for yourself.

Reddeath210

iTrader: (1)

When you say lean, do you mean on fluid?

and what do you mean by no centrifugal, sorry about my lack of knowledge :S

Mike's 87

I have a weiland pump... it works, but disappointed in chrome finish. If you put a large can in you may need an electric vacuum pump (auxiliary ) to provide necessary vacuum for power brakes....so I've found out

Reddeath210

iTrader: (1)

@mike i only have a mid cam from what i am gathering, and from what i was told be a few people. It also doesn't have the large cam sound that everyone has grown to love

Mike's 87

Lean meaning starving for fuel.
If you drive in colder weather do not use low temp thermostat as you will get very little heat because thermostat will open at lower operating temp.
Doesn't sound like fan is issue. Unless not kicking on.
Single to dual setup takes a setup designed for that purpose.. by that I mean, may take more work than you want in order to configure

Reddeath210

iTrader: (1)

@mike is there anyway to check what PSI fuel pump i have in the tank, the car was originally EFI which means that it would of had a 7 PSI fuel pump, since its now carbed it should have a 9 PSI fuel pump is there anyway for me to tell?

Mike's 87

That's out of my realm....I run a TPI and haven't messed with carbs in 20 yrs. As for pump pressure I really don't know how to test pressure on it.

Mike's 87

Why would you downgrade to a Carb?

Reddeath210

iTrader: (1)

I bought the car with most of the engine mods already done to it

Mike's 87

Does it still have computer under psgr dash? Sent you a pm

Mike's 87

1gary

Guys when you consider a good core(most 350's) 350's can be safely bored to .060,030 is nothing.So the idea of a stroker 383 overheating because of thin walls isn't valid.Now the 400's which start as a thin wall block is another story.Some have serious overheat problems and others don't.

It's important to address overheat problems right away.You risk losing your total investment.SBC's will tolerate some issues like that.But only to a point.

Here is what I was saying about bubbles.If you have a cracked head,blown head gasket,warped head,warped block deck,it will seep pressure into the cooling system and bubbles will show up at the rad neck after the stat opens.It might not show up until the engine gets to operating temp where the gap opens up.No do no open the rad cap after it gets hot,but leave the cap off and watch for bubbles as the stat opens.Given the pressurization of the coolant system,it would never run in normal temps.

The other option is to leak it down.You'll hear where it is leaking or not doing that.

The air dam is a common pick and pull item.You should get one in any case.A good rad without a good shroud is useless.

Bottom line,don't treat the symptom,find the cause and cure it.

Reddeath210

iTrader: (1)

Picture of the engine

Reddeath210

iTrader: (1)

@gary to clarify, the best thing for to do is to take the cap off. Then start her, and watch for bubbles till she warms up. If there is bubbles that could indicate a major problem, and if there isn't i can breath easy?

1gary

Want to add a cracked block would do the same-thing too.

Those fans only cool for the most part in traffic slower speeds.Air flow is the major contributor to cooling at highway speeds.Deductive logic says the missing air dam is some of the cause of it getting hot.But it not going back down afterwards is troubling.So maybe two issues and not just one.True enough that antifreeze once hot stays hot longer than water,but it should still come down.

1gary

Yes

Reddeath210

iTrader: (1)

@gary well what will happen is when i go on the turn pike or anything with speed limit 55+ for an extended period of time, my temp will slowly rise. Highest i have seen it rise is to 250. Once I get off, it will drop sometimes. I have gotten off before and it has dropped to 230 within 5-10minutes and then there are times where it will stay at 250.

Now we also thought my gauge could be bad, since my MPH and RPM are both off.

1gary

The way I am thinking about this is:cause-effect-end result.

Lacking the air dam was the root cause the very first time and very well could have happened before you bought it-the effect is the 250 temp and even if the gauge is off some that is way,way, over a limit it should have been heated up to-the effect now might very well be one of those things I listed as needing to be repaired.It is serious enough to create damages that I don't think even running it after installing a aftermarket gauge I would advise you to do.But certainly a aftermarket gauge might help in you diagnose the truth of the matter.The speedo btw has nothing to do with the temp gauge.Many are run off a VSS of the back of the tranny.

Your bottom line is if it ever got anywhere near as hot as 250,there is a high percentage your now dealing with one of the damages I listed or very soon will be,being one of the luckiest person on the planet.

Mike's 87

A couple most likely possibilities also are: bad thermostat, Bad coolant ratio, bad coolant temp sensor. Bad gauge. Definitely recommended is a power flush of radiator and motor and while drained change thermostat and temp sensor. Temp sensor is on side of block (a joy to do with headers, like doing plug change).

Mike's 87

Definitely find a scrap yard and get an air dam. Or look at summit racing.com classic industries.com...... you get the idea

Mike's 87

http://www.classicindustries.com/fir...=1986&p=1&sb=0

Here's a possible part

Reddeath210

iTrader: (1)

:S i hope nothing major is wrong with it >.< i just bought it 3 weeks ago

Mike's 87

Check simple causes first.... thermostat check and coolant level & ratio check and air bubble check. If you have questions on how to do any of these feel free to call or msg me.

1gary

Simple causes I agree with Mike.But now your prepare either way.

Keep us updated.

Mike's 87

By using TGO forums and starting with solutions you can do on your own, you may not resolve the issue at hand, but you will save a lot of diagnostic $$ .

My case as example is a no start.
Check coil & distributor for spark (ZAP!!! yup, got spark )
Replace old cap & rotor
Replace burn off relays
Replace ignition module on distributor
Swap ecu to determine if computer possibly went badlast choices computer chip gone bad or something I can't figure out and tow to shop.

bwiencek

since you said the fan was wired to come on "all the time" - check to make sure it's been wired to run in the proper direction (I've seen guys reverse the wires when they cut them where they run up towards the fender and the fan then runs backwards and you're fighting the natural airflow at speed) Also make sure you don't have a late model "reverse rotation" water pump that normally goes on engines that run the serpentine belts...

Reddeath210

iTrader: (1)

@bwiencek, how would i check which kind of water pump i have, and my engine does run the serpentine belt

And how would i know if my fan is going the right direction?

bwiencek

Water pump isn't real easy to check - the only way I know of is to look at the pump's impeller - if you're talking about the red one in the pic above - it's a standard rotation - the ribbed v-belt is used as a standard belt and doesn't "serpentine" all over and drive the water pump "backwards" In general - if the pulley has grooves it's standard rotation, if it's smooth then it's reverse rotation... Real easy to mess up when swapping engines around and mixing front accessory drive items.

As for the fan - real easy - have someone turn the key on and then off and watch the fan rotate as it slows down you'll be able to tell if the blades are pulling air from the radiator into the engine bay (correct) or pushing air forward and trying to push it through the radiator to the front of the car. Just think about "natural" airflow as you're driving on the highway - if it's pulling air the same direction then you're all good.

NotsosleepyZ

if it was the air damn it wouldn't overheat just sitting there... I would recommend grabbing one however, but im willing to bet that radiator is full of filth on the inside and as I said spray the outside with a pressure washer from a reasonable distance, the get bugs and grime but again wouldn't be the culprit if its over heating that fast sitting there..... it almost HAS to be a water pump problem cause its over heating sitting still...... it should not over heat on idle unless its really hot outside, edelbrock make a good pump, or get an inline electric to HELP the stock water pump. but again IF the water pump is functioning I say its the filthy interior of the radiator and cooling system flushing them help ALOT

Reddeath210

iTrader: (1)

@notso i ran it today for about 5-10minutes and the temp gauge read 180 degrees. So i don't think its overheating just idling.

If i drive it and give a fair amount of gas anything over 45mph she starts to climb. She doesnt go higher then 220 unless i really give her gas

NotsosleepyZ

then definitely try pressure washing your radiator I had the same problem with my first z28 when I was 14 tried everything the radiator was so filthy it couldn't pass air through the fins, but try the flush as well, the flush fluid is like 8 dollars from any auto parts store, and the pressure washer is like 2 at a local car was lol, those are the two cheapest options then look into a water pump and air dam.... IMHO and like someone mentioned above make sure your fans are pulling not pushing air.

Reddeath210

iTrader: (1)

Got an air dam at a junkyard today. only a buck.

Ill tell you guys if anything changes

Reddeath210

iTrader: (1)

So i used to cowl today, and it seemed like when i sped up the car would get cooler as long as i didnt lay into it.

It stayed around 190-200 when i was moving and 210 at a red

1gary

Still 210 is too hot.

Reddeath210

iTrader: (1)

I am going to try flushing it, and cleaning the rad.

Another thing i thought was weird, when i was driving home yesterday i made a right and sped up and my temp went to 220. Then when i stopped at a red light out of no where my time dipped to 180. Then picked up to 190-200 for the rest drive

bwiencek

Sounds pretty normal if you have a 195* thermostat in there which since we're so used to "modern" gauges on the new cars they're a little more than an idiot light - they dampen these fluctuations in the temp as the car warms up and the thermostat is cycling open/shut to try and warm all the coolant... The initial spike to 220 was when the thermostat was getting ready to open for the first time, then it opened and cold coolant rushed in dipped it to 180 when the thermostat closed and then it finally reached a point where the coolant was all about the same temp and stablilized.


Since you have a 383 producing I would expect a lot more power than the stock 305 produced at WOT you will be generating a lot more waste heat that needs to be pulled out with the cooling system - if it only runs hot under heavy acceleration but cools down when you slow down (and produce less waste heat) then it may simply be that your cooling system cannot handle the extra heat capacity of the new engine under a high load/power condition. That usually means you need to do some upgrades to one of the cooling points - larger system coolant capacity, higher coolant flow, higher radiator capacity, higher volume of airflow through the radiator, etc. Most guys will simply put a larger and more efficient/modern radiator and dual fans on to solve the heat capacity problem.

Reddeath210

iTrader: (1)

@bwiencek so your saying since i have a larger engine that produces more power which inturn means i should use a newer cooling system.

So i should look into a better radiator, and dual fans. So when looking into a better radiator what should be the specs i look at to measure between a stock radiator and a high performance radiator