Head Gasket Issue.

**jimnielsen** · 19-09-10, 22:40

I have having an 'experiment' on how to increase boost at high RPM. Unfortunately I ended up with too much boost (enough to separate the exhaust system). I can't say how much boost the system was generating for sure - because the sensor I use collect boost data for the logger maxes out at 1.5 bar - but I was the needle on the boost gauge was on the 'pin' at 1.7 bar. Anyway I think there is a bit of oil in the coolant. So I am concerned that I have indeed damaged the head gasket (car still seems to run fine...)

ok then.. what is the best way to test to see if you actually have a head gasket problem with these engines? I need to find out for sue before I pull the head off the engine.

Regards, jim.

**wrinx** · 19-09-10, 23:57

Only way I know of is to use a "sniffer" fluid which turns a different colour if there's combustion gases in the coolant.

But there's bound to be a more high tech way

Btw...I had free boost from my turbo a while ago and also think I may have a duff HG because of it

wrinx

**jimnielsen** · 20-09-10, 21:58

well, I have had a careful look over the car, and I can't really determine if there is a head gasket issue of not, - compression is 200, 202, 200 205 - so that's fair enough. I have a friend who has a hydrocarbon test kit, so I will try that out today.

jim.

**SteveNZ** · 21-09-10, 08:16

Hydrocarbon test but its not full proof, can give false positives and false negatives. It depends how the gasket is blown.

You can also do a leak down test. Fill the cylinders with compressed air and see if any leaks out into the coolant.

**WhizzMan** · 21-09-10, 09:00

You can have leaks from or to water, combustion chamber and oil. That makes a lot of combinations possible as to what can leak to what else.

Your compression seems fine.

Do you have water in your engine oil? check by holding a flame to the end of your dip stick. If you just pull it out, there should be some oil on it. Heat that, if it "sizzles" there is water in it boiling.

You already said you have a little oil in your coolant. Are you certain that is a "new" issue, or could it have been there much longer? Is your turbo water cooled? If so, it could also be leaking through the turbo and it could be a non related issue. Does the oil in the coolant seem to get worse, or can you just scoop it out and it doesn't come back in your expansion tank?

Any smoke in your exhaust fumes? White/blue?

If all seems to be fine, I wouldn't pop the head if it was a street car. On a race car it's harder to make a decision. You will be riding this hard and if you have a minor seepage going on at full boost, it will probably get worse during racing and might evolve into a full blown gasket. At the price of a gasket, I might not want to risk this.

**1NRO** · 21-09-10, 17:17

Oh go on Jim, take the head off so I can see what those pistons are doing

Another on those mentioned already is to pressurise the coolant system if you can get the tool http://cgi.ebay.co.uk/SYKES-PICKAVAN...item1e5e473e3c

**wrinx** · 21-09-10, 20:46

Originally Posted by 1NRO

Oh go on Jim, take the head off so I can see what those pistons are doing

Another on those mentioned already is to pressurise the coolant system if you can get the tool http://cgi.ebay.co.uk/SYKES-PICKAVAN...item1e5e473e3c

Bugger! I was looking for a pressure tester a while ago, they all went for silly money...?26!

wrinx

**jimnielsen** · 21-09-10, 23:19

Thanks for all the suggestions, I really appreciate them! A friend of mine has a 'Snap-On' C02 tester for the cooling system. I very carefully prepared the blue fluid like it says in the manual, making sure that I could turn the top blue tank 'yellow' with by exhaling a little into a cupped hand. However it refuses to turn even the smallest bit yellow when sampling the air above the coolant after the car has been running.

I guess the whole idea of the car having a head gasket problem came about because of the fact that I had been running boost too high (though not at wide open throttle) - as soon as I saw that boost was way out of control, I was trying to get back around the track too get the car back to the pits..Normally I would do a 'cool-down' lap after running the car hard - but this time because the car was making quite a bit more noise than usual - combined with the boost 'issue' I just took the car around the rear of the pits and turned the engine off. So the engine was pretty warm (but coolant temp was still south of 90 degrees) - this could account for the fact that the coolant top tank bled off about a litre of coolant. Then when I opened the top tank I was just focused on the fact that there was a little oil around the inside rim of the tank..so I decided that there must be a head gasket problem.

But really I don't have any more evidence for there being a problem than that! That being the case, and the fact that I only have one more event left this year - makes it difficult to decide to remove the head. I think that before I could justify doing that I'd have to take the car out to the track for a test drive (or on a dyno..). I do have a complete leakdown test system as well - but haven't used it yet.

pics.. CO2 testing, new shed.. just moved the hoist yesterday!! The first data pic is a graph of RPM and boost on the problem run. The last two compare the water temp data from the problem run (water1) and a normal run (water2). In water1 - the car is stationary after 384 seconds with the engine running.

**jimnielsen** · 21-09-10, 23:28

rest of the pics

**1NRO** · 22-09-10, 07:28

Nice shed Jim

**WhizzMan** · 22-09-10, 07:53

You have at least two tests showing you do not have compression loss. It seems you don't have a lot of oil getting in to the coolant, if at all. 99.9% chance you are just being paranoid about the gasket.

26 UKP is a good price indeed, wish I could get one for that.

**jimnielsen** · 11-02-11, 10:15

I took my car into Beninca Motors today to put on the dyno to configure the Autronic SM4. That part of it went very well, but unfortunately towards the end of the session we discovered the root cause of the 'head-gasket' problems that I have been having. In fact, there is a big crack in the block in #2 cylinder. They have a very high end endoscope and you could clearly see the fissure that has developed and the water coming out of it into the cylinder.

Bad news, really

- anyway next week I need to strip the engine and take the block in to have it sleeved! I have a race in three weeks - but it will really be a race to get it all reassembled in time!

[ame="http://www.youtube.com/watch?v=SbFFr2SCYC0"]YouTube - Dyno Tune SM4[/ame]

jim!~

**AlfaJack** · 11-02-11, 10:26

Bad luck Jim. At least you know now.

Did they manage to do a power run or were you just setting things up still?

**Steve Webb** · 11-02-11, 11:10

Jim, are you just going to sleeve it or are you going to do anything about the crack as well?
Is there anywhere near you that does metal stitching? Sort of like a belt and braces approach to the problem.

Metal stitching

Bad luck by the way.

**jimnielsen** · 11-02-11, 11:35

well, I will take it to my engineering workshop and we will come up with a plan.. but I suspect that we will just sleeve the single cylinder and then reassemble the engine!

**Steve Webb** · 11-02-11, 11:41

Good luck with it all, 3 weeks isn't a long time to get it all back together, and get the SM4 mapped as well.

**jimnielsen** · 11-02-11, 11:55

We have pretty much finished mapping the sm4,
So that won't be a problem.

Jack - 290 hp @ 1.1 bar boost - injectors are maxed!

**Steve Webb** · 11-02-11, 12:00

Didn't you have a spare engine Jim?

**jimnielsen** · 11-02-11, 21:23

yes, I do have a spare engine - and I may use that block, but it would be nice to still have a spare engine by not using it now

**jimnielsen** · 12-02-11, 07:16

some disassembly progress - fortunately I remember how it comes apart as it was not that long ago that I put it together! Perhaps I will have the engine out on the ground by tomorrow...

**Steve Webb** · 12-02-11, 08:57

Look on the bright side Jim. Pulling it all apart this often means you won't come across any seized bolts.

**wrinx** · 12-02-11, 15:54

Bugger...bit of a pain after all your hard work.

Hope it's sorted in time

wrinx

**jimnielsen** · 13-02-11, 06:41

Well, engine is 'out' - the crack looks bad! All told it took me about six hours to get the engine out - I cant believe how many things you have to undo and remove - and my car hardly has any stuff left anyway. I hope to get the engine stripped back to the block tomorrow - so that I can take it to the reboring place...

Hard to believe it was making damn near 300 hp at the wheels with that crack!

jim.