273 Coolant leak help

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4spdragtop

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Well I was noticing some issues with the engine temp on dads cuda. Started late last year, overheated(failed t-stat) last year. Replaced t-stat(with jiggle valve) and tested before install. But gauge was now always pegged. Replaced coolant temp sensor(stock). Still pegging gauge. Replaced gauge this year and everything was good. Ran hot a bit on 90* day, engine was around 220* on gauge. Boiled some water/coolant out and had to add a couple litres to top up. I thought screw it, I had a spare 7 blade fan and swapped it in exchange for the 4 blade. While in their I figured I may as well remove the factory ac condenser as its blocking air flow to rad. It was tempting to leave it in as it offered "protection" for the factory rad. Rad was in great shape. We sent it to a shop and had it dipped and psi tested when dad bought car in 2012.
I stripped, straightened fins and repainted rad. Topped up with new coolant and distilled water. 70 coolant 30 water. Fired it up, added a bit more coolant and noticed a leak down on ds. Initially wasnt much with rad cap off, but once engine was up to temp with cap installed it got a lot worse! Checked engine oil dipstick and no coolant there.
Initially it looked like behind the timing cover, but would coolant be coming from there?? Im sure as hell hoping its not a head gasket.
Heres a video
Thanks for the help.

 
Steve, the timing cover and inside of the engine are VERY close to each other where the coolant goes through the ports on the timing cover.
It may very well be leaking where the block and cover come together, and it is even fairly common.
That being the case the head gaskets don't have anything to do with it, and a simple re gasket would seal it up.
It's also real common to be able to just tighten the water pump bolts up a bit and stop it.

I think you need to narrow that down, as it's hard to tell exactly where it's coming out from.
Could be intake, timing cover or head gasket, though leaking head gasket rarely leak that much.
Dry it off good and watch it REALLY close even if you have to use a mirror, but per the video it looks like the intake corner is what's leaking.
Can you tighten it down just a bit and see if it helps slow it down?
 
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I'll try and snug em up. If not lets hope for front leak, but if that's the case it could end up leading to an oil pan gasket lol.

Thanks!
 
I'll try and snug em up. If not lets hope for front leak, but if that's the case it could end up leading to an oil pan gasket lol.

Thanks!

The timing covers usually leak right under the top bolt between the block and the cover farther under where yours looks like.
To me it looks like it's coming from right in the corner where all three come together (head, cover and intake)
If that ends up being the case it's the intake gasket corner where the coolant passes though the intake.
Evenly all the way around the intake, tighten it just a 1/8 to 1/4 turn on the bolts but start at the center of the intake and work your way out to the ends so it doesn't try to snap the corner off.
 
I tried snugging up intake and wp bolts but it still sprays out pretty good. Got magnifying glass out and sure looks like its from timing cover. I guess thats better than intake or cyl head. I'll have to order some gaskets up. I hope this doesn't snowball lol
 
In a few cases, that water leak started with water pump R&R. Tightening them more never saved me either. Gasket failure, plain and simple ( or maybe not so simple ).
If the timing cover isn't pitted terribly a gasket kit will fix it. Many of the long bolts go into water jackets. Lets hope none are rusted so bad they break before backing out. Wire brush those bolts, clean and dry their holes, put sealant on their threads.
Snowballing ? How about a new timing set while in there ? Spring loaded chain tensioner too ? :) Good luck with it.
 
I think its corrosion/gasket failure. Once disassembled, I'll sandblast and inspect. Timing chain amd gears has maybe 8k on them. Good point about the tensioner. I may look into that.
Thanks again.
In a few cases, that water leak started with water pump R&R. Tightening them more never saved me either. Gasket failure, plain and simple ( or maybe not so simple ).
If the timing cover isn't pitted terribly a gasket kit will fix it. Many of the long bolts go into water jackets. Lets hope none are rusted so bad they break before backing out. Wire brush those bolts, clean and dry their holes, put sealant on their threads.
Snowballing ? How about a new timing set while in there ? Spring loaded chain tensioner too ? :) Good luck with it.
 
I think its corrosion/gasket failure. Once disassembled, I'll sandblast and inspect. Timing chain amd gears has maybe 8k on them. Good point about the tensioner. I may look into that.
Thanks again.
I'm not sure adding the tensioner is a good plan where everything has already developed a wear pattern.
 
Finally got the time to tear off the frontof the engine.
Couple questions.
#1 Do I replace oil pan gasket?? It appears in good shape and oil pan has not been removed.
#2 Should I install drip tab? Chain and gears are from Comp and only around 8000 kms on it. It also looks in good shape. Obviously if I go with drip tab timing chain and gears have to come off. Wondering if there is enuf of a benefit?

Thanks all
Steve

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You should be fine with the pan, just carefully place and seal your new gaskets.
The oil drip tab couldn't hurt, but at least you have the slinger on the crankshaft so whatever makes you feel good on that one.
Was it obvious where the coolant leak was coming from when you pulled the cover?
 
Thanks TB. When facing engine it was leaking at approx 2 oclock, right beside coolant hole. Looks a little rusty on timing cover. I'll sandblast the cover, wire wheel the engine and RTV. Well see how it looks after sandblasting.
I'll check wreckers for drip tab. What year engine for drip tab?

Thanks!
You should be fine with the pan, just carefully place and seal your new gaskets.
The oil drip tab couldn't hurt, but at least you have the slinger on the crankshaft so whatever makes you feel good on that one.
Was it obvious where the coolant leak was coming from when you pulled the cover?

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The crank shaft seal allows very little upward movement of the timing cover. So getting onto the pan lip aint easy. I have used a couple of long drifts through bolt holes to lift the timing cover, and made it happen but... I risk damaging the shaft seal when doing that.
Hell of a lot easier with GMs little sheet metal cover. I pull their 2 dowel pins and poke my drifts in those holes. Piece of cake.
Gamble, get lucky, pat yourself on the back, versus start over.
 
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Thanks TB. When facing engine it was leaking at approx 2 oclock, right beside coolant hole. Looks a little rusty on timing cover. I'll sandblast the cover, wire wheel the engine and RTV. Well see how it looks after sandblasting.
I'll check wreckers for drip tab. What year engine for drip tab?

Thanks!

Yep, that's obvious alright. LOL
Pretty much any year small block would have a drip tab (or not):D
Let's say pretty much any small block could have one, and as far as the cover I have seen a lot worse than that be just fine when redone.

The crank shaft seal allows very little upward movement of the timing cover. So getting onto the pan lip aint easy. I have used a couple of long drifts through bolt holes to lift the timing cover, and made it happen but... I risk damaging the shaft seal when doing that. Hell of a lot easier with GMs little sheet metal cover.
Gamble, get lucky, pat yourself on the back, versus start over.

Good point, and I also use something to help press the cover down (Two big flat blade screwdrivers) in the two very top bolt holes.
I get them started in the bolt holes flat then turn them where the blade is vertical and it pulls the cover down into place.
Sometimes even pulling down on the handles once the screwdrivers are in there helps, and then I like to get two of the lower cover bolts in it snug to hold it in place while I assemble the water pump and brackets. (and obviously the two pan bolts that were removed.)
Since the balancer isn't on yet when the cover goes on there is a little playing room for the seal, with a bit of caution.
A little sealer or even just oil on the pan seal surface of the rounded bottom of the timing cover helps let the cover slide down into place also.
 
Thanks guys I'll chk with local wreckers for the tab. I had planned on rtv on the tc rounded bottom also. I hope to be able to wrestle it on.

Thanks again
 
Got it all back together finally. Car has sat more than its been driven this summer.
A few drips but nothing drastic. One thing I did was put heatshrink on the hose clamps to try and give it a "cleaner" look. But it seems to me anyway that it could be part of the reason for the drips(see pic of hump hose)

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Is that the proper hose nipple ( has a bulge that the clamp sits behind ) ? It doesn't look right to me.
If its just a pipe fitting, are there pipe threads inside the under the hose ?
Maybe just shoving the hose on the fitting further will cure it. good luck
 
Is that the proper hose nipple ( has a bulge that the clamp sits behind ) ? It doesn't look right to me.
If its just a pipe fitting, are there pipe threads inside the under the hose ?
Maybe just shoving the hose on the fitting further will cure it. good luck

Good point..

Steve, read my thread on hose clamps here and see if you can improve the seal on yours:

Hose and Hose Clamp Basics
 
Good eye Ben. Both of them that the hump hose connects to are bushings/nipples with pipe threads.
Not ideal but next best to orig style fittings. I tried looking for proper ones with no luck.
Pretty sure I've got the leaks fixed now.

Is that the proper hose nipple ( has a bulge that the clamp sits behind ) ? It doesn't look right to me.
If its just a pipe fitting, are there pipe threads inside the under the hose ?
Maybe just shoving the hose on the fitting further will cure it. good luck

Thanks Karl, Im good with clamps, its the nipples and/or the heat shrink on the clamps.

Thanks guys
 
[QUOTE="4spdragtop, post: 1971367944, member: 11349" Im good with nipples and heat shrink.[/QUOTE]

Fixed it for ya... Giggity, giggity... :rofl:
 
Got it all back together finally. Car has sat more than its been driven this summer.
A few drips but nothing drastic. One thing I did was put heatshrink on the hose clamps to try and give it a "cleaner" look. But it seems to me anyway that it could be part of the reason for the drips(see pic of hump hose)

I've got heatshrink on my hose clamps also. Never a problem with leaks & I really like the cleaner look...
 
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