Head Gasket Issue.

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19-09-10, 21:40
jimnielsen

Head Gasket Issue.

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.
19-09-10, 22:57
wrinx

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
20-09-10, 20:58
jimnielsen

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.
21-09-10, 07:16
SteveNZ

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.
21-09-10, 08:00
WhizzMan

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.
21-09-10, 16:17
1NRO

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

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
21-09-10, 19:46
wrinx

Quote:

Originally Posted by 1NRO

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

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! :roll:

wrinx
21-09-10, 22:19
jimnielsen

3 Attachment(s)

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.
21-09-10, 22:28
jimnielsen

3 Attachment(s)

rest of the pics
22-09-10, 06:28
1NRO

Nice shed Jim :8
22-09-10, 06:53
WhizzMan

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.
11-02-11, 09:15
jimnielsen

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!~
11-02-11, 09:26
AlfaJack

Bad luck Jim. At least you know now.

Did they manage to do a power run or were you just setting things up still?
11-02-11, 10:10
Steve Webb

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.
11-02-11, 10:35
jimnielsen

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!
11-02-11, 10:41
Steve Webb

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.
11-02-11, 10:55
jimnielsen

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!
11-02-11, 11:00
Steve Webb

Didn't you have a spare engine Jim?
11-02-11, 20:23
jimnielsen

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 :)
12-02-11, 06:16
jimnielsen

1 Attachment(s)

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...
12-02-11, 07:57
Steve Webb

Look on the bright side Jim. Pulling it all apart this often means you won't come across any seized bolts.
12-02-11, 14:54
wrinx

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

Hope it's sorted in time :)

wrinx
13-02-11, 05:41
jimnielsen

4 Attachment(s)

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.
13-02-11, 12:42
wrinx

Huuuuge! Is that daylight I can see?

wrinx
13-02-11, 16:06
1NRO

:ohmy: feck, that's bad news, hope you get it sorted in time. Shout if you need anything.
13-02-11, 18:47
AlfaJack

Has this been seen on other Lampredi blocks? Is it down to the sheer amount of full on power it has had on track?
13-02-11, 19:55
jimnielsen

Jack, I think its really down to an overboost situation that occurred last year. I was convinced it was a head gasket problem.. but no. I saw this 'crack' when I took the head off to replace the gasket a couple of weeks ago. - but though it was just a scratch from some foreign matter - it looks worse now..

We only did one lap with the overboost - of probably 2.2 - 2.5 bar. I don't think this would have been a problem, but we didn't have the injector capacity to provide the fuel for that much boost..blew the exhaust off the car though..
13-02-11, 23:05
AlfaJack

Quote:

Originally Posted by jimnielsen

Jack, I think its really down to an overboost situation that occurred last year. I was convinced it was a head gasket problem.. but no. I saw this 'crack' when I took the head off to replace the gasket a couple of weeks ago. - but though it was just a scratch from some foreign matter - it looks worse now..

We only did one lap with the overboost - of probably 2.2 - 2.5 bar. I don't think this would have been a problem, but we didn't have the injector capacity to provide the fuel for that much boost..blew the exhaust off the car though..

Are you running a different MAP sensor? The OEM ECU should not allow anything about 1.5 bar.
14-02-11, 04:42
jimnielsen

at the time I was not using the pierburg valve/IAW P8 to control boost - so the boost level was not under its control, even though I was using the standard MAP sensor for fueling etc..
14-02-11, 07:24
jimnielsen

5 Attachment(s)

Pistons out..

I removed the pistons from the cracked block today - the good news for me is that they are still just fine - a testament to how robust they are! But I did get a big surprise - two of the oil squirter necks had been broken off by the lower inside skirt of the piston - they were just rattling around loose in the motor!!

There are a few tiny dents in the underside of a couple of the pistons - but this could have easily been fatal. You can see in the pics how the pistons have been hitting all of the squirters so I was lucky that they didn't all break and cause a catastrophe. I don't believe that the oil squirters being broken and the block cracking is related. The crack is 5" long and you can even see it from the water jacket side!
14-02-11, 07:42
Steve Webb

How much clearance was there between the pistons and squirters when you spun the motor round by hand? Is it just down to reduced tolerances when at high rpm or do you think something moved in there.

Like you day, I can't see the squirters having anything to do with the crack.
14-02-11, 09:52
SteveNZ

Quote:

Originally Posted by jimnielsen

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!

Thats bloody good power Jim. pity about the block. I'll have a ask around fr a block
14-02-11, 10:05
jimnielsen

Thanks Steve! I appreciate it...

jim~
14-02-11, 10:17
jimnielsen

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Steve (webb) - this is the only picture that I have from original assembly that shows a piston (#1) and the oil squirter together. It is close, but I can't remember whether I saw that and thought it would be ok, or just didn't realize that I didn't have enough clearance. There is plenty of room in which to bend the squirters - and I will do just that. I think that with E85 and the very low internal temperatures that the squirters are not needed anyway...

jim..
17-02-11, 09:48
jimnielsen

1 Attachment(s)

new injectors

My new injectors have turned up today... I am currently using the Siemens Deka IV 630cc injectors (384cc is standard). I am changing to the Siemens Deka IV 875 cc/min.

Its amazing how much fuel you need with E85!

jim
17-02-11, 10:46
Steve Webb

Might have missed it, but why are you using E85 Jim? Is it for the higher Octane rating or cooling?

And what sort of mileage do you get from it?
17-02-11, 20:15
jimnielsen

Steve I use it purely because is has excellent protection against detonation for turbo engines. Its also much cheaper than ELF racing fuel!

I am getting about 2km per litre. In a normal configuration E85 cars use about 1.3x volume as petrol cars - but race cars can use 1.6 times because they can be run richer and still run well.. This is why I need new injectors..

384 x 1.6 = 615 - that's 97% of the 630 cc/min that my current injectors can deliver - and on the dyno they were running at 97% capacity! The system was working but there is no headroom for 'fuel trims' - ie to add more fuel if the engine gets hot (etc) And obviously no more fuel to enable boost increase...
17-02-11, 21:53
Steve Webb

I was just asking because of the lower energy content of the E85, but the higher octane of it means you can use more compression/boost.
Are you going to have a switch able map, just in case you need to run it on pump fuel?
17-02-11, 22:38
jimnielsen

no I'm not planning on that steve, but with the Autronic that would be very simple, you could actually make an alternative fuel table and activate it with a physical switch. I am running 9.2:1 compression however, so I would not want to run too much boost on pump fuel..