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3800 S2 blown head gasket? by Frenchrafe
Started on: 05-25-2020 10:18 AM
Replies: 15 (243 views)
Last post by: Frenchrafe on 06-15-2020 11:44 AM
Frenchrafe
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Report this Post05-25-2020 10:18 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hello all 3800 experts! Some advice please?

Symptoms:
Engine shut down on a hot day. Engine temp light on (intermittent), SES light on, engine refused to restart when hot. However, the temperature gauge wasn't even showing very hot!? (Bad sensor?)
No obvious coolant leaks or extream pressure in the hoses, however some gurgling noises coming from the block/heads.
Slight brown residue on inside of radiator cap and same on the inside of the overflow tank. (Could just be old rusty residue that got flushed, but it seemed rather greasy?)

I did a coolant purge once the car got home, but nothing seemed that bad, ie: no huge amounts of air in the system. Car ran like s*** and the engine temp light and SES light came on again. I did notice that the upper hoses and lines were hot so the thermostat was OK, but the return side seemed very cool. The cooling fans were running of course.

My thoughts:
Head gasket blowby putting some oil and exhaust gasses into the coolant? However, the spark plugs are perfect colour - no oily residue. Compression test on cylinders OK. So it doesn't seem that the gasket is totally blown into the combustion chamber? (Cometic multi-layer gaskets by the way.)
Restriction in the cooling circuit not allowing enough flow? Water pump failing and/or cavitating? Restriction in the pipes and or hoses? (Nothing obviously damaged underneath the car for the long rigid coolant pipes.)

Your thoughts and/or advice?
(Before I start stripping down the engine and cooling system.)

Thanks in advance,
Rafe


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"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!

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Dennis LaGrua
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Report this Post05-25-2020 03:02 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
Difficult to say what is happening but a head gasket leak usually discolors a plug or two and can blow coolant out the exhaust. If you do a pressure test of the cooling system and it doesn't hold pressure, that can indicate a leaky head gasket.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Steel
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Report this Post05-26-2020 07:06 AM Click Here to See the Profile for SteelSend a Private Message to SteelEdit/Delete MessageReply w/QuoteDirect Link to This Post
Are you sure you got the air out of the cooling system with your purge?

Top off the rad, remove the t-stat, top off the level from the rear, put the rear cap back on and start the car. It takes me 3-4 tries to get the air out of the rear of the car.

Otherwise I'd be looking at a bad radiator cap or waterpump before I went into deeper/larger issues.

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Spoon
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Report this Post05-26-2020 12:55 PM Click Here to See the Profile for SpoonSend a Private Message to SpoonEdit/Delete MessageReply w/QuoteDirect Link to This Post
You overheated the engine twice, both times with 2 red warning lights in full view plus the audible sound of gurgling water. Your diagnostics confirmed that the top radiator hose was hot to the touch and the return hose was very cold and the coolant fan was rev'd up trying to save the day.

My guess would be bad t-stat, bad impeller on water pump. A missing belt would reveal additional warning lights so that's not the case.
Remove the thermostat, start engine and check both radiator hoses again. Both should become warm. If that is true you need a new T-stat.

If you did any damage by overheating I would suspect a head gasket, possibly both. TTY head bolts are already stretched on a good day and when you overheat an engine the metal expands which stretches those bolts even more to the point that they will not recover so with less clamping effect the gaskets leak. I recall reading that from some of the North star articles.

Pull your plugs like mentioned by others and check for color. You can also remove your radiator cap and observe the level while someone cranks the engine over when it is cold. (less clamping effect of the heads to the block) and if you see bubbles or surging of the coolant its time for a rebuild, IMO...

Spoon

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"Kilgore Trout once wrote a short story which was a dialogue between two pieces of yeast. They were discussing the possible purposes of life as they ate sugar and suffocated in their own excrement. Because of their limited intelligence, they never came close to guessing that they were making champagne." - Kurt Vonnegut

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Frenchrafe
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Report this Post05-26-2020 01:38 PM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks for all these good replies.

Yes it did get hot, but no I didn't push it once the lights came on - I just coasted to side of the road. As well the ECU cut everything very quickly and I couldn't restart for long time.
My temperature gauge gave no warning at all! And I'm a racer so oil pressure and engine temp are like second nature for me to watch while driving. Like I said before, it was only the red light (engine temp warning) and the check engine that gave the signs. Then the car cut out.

I am inclined to think water pump and/or lack of flow? If it was a bad T Stat, wouldn't that keep the heat away from the top hoses? Just until the steam pressure burst through! They were full of coolant, albeit hot coolant.

When I accelerate, that's alot of extra "force" keeping the coolant towards the rear of the car. If the flow is bad or the pump can't overcome this force then the coolant stagnates in the heads and block. It has more time to superheat and then maybe pass into gas phase locally - thus the gurgle I heard.
Which would add to the problem with a sort of "vapour lock" in the heads. Though like i said as well, there didn't seem too much gas/air when repurged?

For the bad running afterwards, I probably "cooked" my already overdue and heavily raced spark plugs. (They will get changed out before the next trackday!)

So I think I'm going to start with just dismanteling and checking every hose and pipe going from the engine towards the radiator. I'l test the T stat as well.
Afterwards, if all hoses and pipes OK, the water pump...

I'll keep you informed of what I find...

Regards,
Rafe

------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

[This message has been edited by Frenchrafe (edited 05-26-2020).]

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Report this Post05-26-2020 04:16 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
I'll put my money on a broken pump impeller. Surprised it isn't leaking.
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Report this Post06-08-2020 03:24 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hello all,
Well the pump isn't dead. In fact it seems totally OK. (Which is a shame 'cause I ordered a new one along with loads of other little bits-n-pieces!)
New pump is in - just to be sure!

The thermostat seemed to open at 82°C (180°F) when tested in a hot water bath (cooking pot on the stove!)
I then compared it's fonction with the new one, ordered above, and they both opened at around the same temperature. However, the new one seemed to move further and have a better "opening" at all temperatures. Even when coming back down in temperature, the new one kept it's opening larger.
I hope this was part of the trouble.

The coolant sensor (ECT) seemed a bit "iffy" when tested. It didn't read exactly the same resistances throughout it's fonction compared to the new one. Could have thrown the engine hot code?
It's been changed out as well now.

Since I was going through all the possibilities of the cooling system, I replaced the front radiator hoses as well. (More so insurance for the next race as the old hoses were OK but original.)
While the hoses were off, the rear to front pipes were inspected and I forced my "toilet pipe un-blocker tool" to clean any restrictions in the pipes. There were none!

So now the system is put back together, with new parts, and is ready for startup.
Spark plugs were replaced as well along with a couple of other little things.

I'll let you know how it turns out...

Rafe


P.S. I filmed some of my time in the garage - style voice over blog - but I haven't had the time to edit. It'll be posted later, maybe...!?


------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

[This message has been edited by Frenchrafe (edited 06-08-2020).]

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Frenchrafe
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Report this Post06-13-2020 10:39 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
I think it's my aftermarket aluminium radiator!

Top engine hose gets hot quickly after start up. Thermostat opens fine - checked on hot engine, was wide open.
But front upper radiator hose takes some time to warm up. The left side radiator tank will get warm eventually, but not as hot as the engine hose or the top radiator hose.
Right side radiator tank stays cold/lukewarm along with the return pipe and the lower engine hose.
However, the water pump gets to the same temperature as the block. I should be seeing a slightly lower temperature on the pump and it's inlet/return.

Fans come on at desired temperature but stay on far too long, especially at idle. The scantool showed not that much drop in temperature with the fans on.
In fact, the engine continued to climb 1 or 2° in temperature while the fans run - not logical!

I've read some bad revues of the "Champion" aluminium radiators. It seems that the passages are too small and can easily get clogged.
After which the radiator doesn't flow!

I think that's my problem.

My other problem is that I've spent my yearly "play car" budget already; going to need to negociate with my "co-pilot" for an extension!!

Regards,
Rafe

------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

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Dennis LaGrua
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Report this Post06-13-2020 12:14 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Frenchrafe:

I think it's my aftermarket aluminium radiator!

Top engine hose gets hot quickly after start up. Thermostat opens fine - checked on hot engine, was wide open.
But front upper radiator hose takes some time to warm up. The left side radiator tank will get warm eventually, but not as hot as the engine hose or the top radiator hose.
Right side radiator tank stays cold/lukewarm along with the return pipe and the lower engine hose.
However, the water pump gets to the same temperature as the block. I should be seeing a slightly lower temperature on the pump and it's inlet/return.

Fans come on at desired temperature but stay on far too long, especially at idle. The scantool showed not that much drop in temperature with the fans on.
In fact, the engine continued to climb 1 or 2° in temperature while the fans run - not logical!

I've read some bad revues of the "Champion" aluminium radiators. It seems that the passages are too small and can easily get clogged.
After which the radiator doesn't flow!

I think that's my problem.

My other problem is that I've spent my yearly "play car" budget already; going to need to negotiate with my "co-pilot" for an extension!!

Regards,
Rafe



If you believe that the radiator is clogged, remove the coolant and the hoses. Then rig up a way to get garden hose pressure through there and see how it flows. I use a radiator flush kit but some of the big box home material stores sell hose plugs in the plumbing section that can be adapted.

------------------
" THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP /Frozen Boost Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Spintech/Hedman Exhaust, P-log Manifold, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, Champion Radiator, S10 Brake Booster, HP Tuners VCM Suite.
"THE COLUSSUS"
87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H
" ON THE LOOSE WITHOUT THE JUICE "

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Frenchrafe
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Report this Post06-14-2020 02:44 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks Dennis, yes I have flushed the radiator using garden hose fittings and pipe deblocker solution! (We call it "Destop" in France - it's pretty corrosive and cleans really well!)

So I'm just wondering if my heater hose routing and turbo cooling is not taking all the (easy) flow for the cooling system?
Leaving the engine block with very little coolant flow?

As has been pointed out previously, this is not the first time I've had overheating issues!


Do cars fitted with 3800 engines have restrictors or valves for the heater circuit?
As I explained in my build thread, this engine was hard to come by in Europe and I didn't have the donor car to check this kind of thing.

Maybe I've always had bad flow because the heater circuit takes priority and nearly nothing is pushed through the block?

When I routed the hoses, I capped the heater return on the right hand side rigid front to rear pipe. This was because there is a return inlet on the 3800. So I just used this.
I'm thinking maybe I just made a rather effective engine coolant bypass circuit by mistake !?

Pics of cap and heater return reroute:



Pic of 3800 heater outlet and return, as on my engine:



It doesn't involve a big mod to cap the return inlet on the engine and reroute a short length of heater hose from the rigid heater return pipe back to the original position.
I may well try fitting a restrictor in the heater pipe outlet at the engine as well.

Stay tuned…

Rafe

P.S. I know there are drops of coolant in the photos, I'd just refilled the system and managed to splash everywhere!
------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

[This message has been edited by Frenchrafe (edited 06-14-2020).]

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Frenchrafe
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Report this Post06-14-2020 10:19 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
OK, 3800 heater return blocked off (still have my turbo water feed, but it's small diameter tube):



Put back the heater return pipe as original:



And made a 5mm restrictor to go in the heater feed hose. (I use a tee at this point to fill my coolant system as it's the highest point):




Everything is back together and purged now. However, it's Sunday afternoon and there is nobody making any noise like lawnmowers, DIY work, etc... so I can't annoy the neighbours with the Fiero idling in my garage! I'll be the only one making noise pollution.

I'll start it up and run it to temperature tomorrow...

Regards,
Rafe

------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

[This message has been edited by Frenchrafe (edited 06-14-2020).]

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Frenchrafe
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Report this Post06-15-2020 08:15 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Problem solved!

And I'm a numpty, plonker, wally and twit all rolled into one!!!

Everything is circulating as it should. The car gets to temperature quickly and then stays there.
Fans come on at 87°C (189.5°F) and then the temperature drops as it should.

How this poor engine kept cool before, with my crappy hose routing, is anybody's guess? I recon air flow while driving and just convection in the cooling system kept it just about OK, except for the hard days at the track or when the air temps were very high.
(Like when I got the shutdown that started this thread - the ambiant air temperature was at 30°C. Very hot for the saison here in northwest France!)

Best regards,
Rafe

------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

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Gall757
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Report this Post06-15-2020 09:28 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post


Can't quite picture what went wrong. Did your coolant go through the water pump but not the block?

[This message has been edited by Gall757 (edited 06-15-2020).]

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Frenchrafe
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Report this Post06-15-2020 10:48 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Gall757:

Can't quite picture what went wrong. Did your coolant go through the water pump but not the block?



Yes, the water pump was pushing nearly all through the heater matrix with hardly any flow through the block.
The 3800 seems to have a very free flowing circuit for the heater! It seems the fluid dynamics preferred the easy route!

Regards,
Rafe

------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

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Gall757
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Report this Post06-15-2020 11:23 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Maybe the radiator is getting more restrictive. Corrosion?
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Frenchrafe
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Report this Post06-15-2020 11:44 AM Click Here to See the Profile for FrenchrafeClick Here to Email FrenchrafeSend a Private Message to FrenchrafeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, that as well.
That's why I stripped down all the system and did a chemical and pressure flush on the radiator to hopefully eliminate some of the corrosion and/or deposits in the radiator.

Regards,
Rafe

------------------
"Turbo Slug" - '87 Fiero GT. 3800 turbo. Sticky tyres. Driven hard!
https://www.youtube.com/cha...1wZvWQlkYxTjivW_0XNg

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