Cracked Cylinder Head - Negative

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chalky

Cracked Cylinder Head - Negative

Post by chalky » Fri May 07, 2010 8:42 pm

Hi,

You may remember me from a few weeks ago regarding a suspected cracked cyliner head on my very well maintained SGL-3 with 60K miles. Well, I had it into the garage this week and they confirmed to me that there is nothing wrong with the head and no exaust gases have been found in the coolant. However, they do not know what is wrong with it.

I have just ordered some dye and and ultra violet light online and I'm gonna get uder the damn thing myself untill I find that leak.

The fact still remains that it is still using the coolant. However, still dont know why. Compression test and pressure tests were fine. I have been monitoring it over the past weeks and it has used around a litre of coolant. But, this is not regular as on one long trip it uses nothing then on another very similar trip, it suddenly uses loads. I'm going bl**dy mad here trying to find the solution and the garage cannot help.

So its back to you guys. Why would a car use coolant on one trip and not another. I would really appreciate a resolving answer on this tonight if possible (lol) as I am still booked to drive to Sitzerland on the 28th.

HEEEEEEEEEEELLLLLLLLLLLLLLPPPPP!!!!!!!
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gmaczbongo
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Re: Cracked Cylinder Head - Negative

Post by gmaczbongo » Fri May 07, 2010 8:56 pm

It maybe using coolant all the time.
It is just airlocks that are stopping it showing in the expansion tank.
When the airlock is removed or moves itself, it finally shows in the tank as big water loss.
If it is not leaking outside the engine, then it must be leaking inside the engine.
Is the exhaust showing white smoke at any time.
Are you pressure testing when engine is hot.
phoenixroxy

Re: Cracked Cylinder Head - Negative

Post by phoenixroxy » Fri May 07, 2010 10:13 pm

im sure you must have checked already, but i had a small leak from the waterpump tell-tale hole and it was really hard to spot. worth a look if you haven't already.
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Re: Cracked Cylinder Head - Negative

Post by David Edwards » Sat May 08, 2010 12:14 am

I have been having similar problems with mine lately and all tests have been done same as you with negative results, today I went to my local breakers yard re a radio and to be fair the mechanic there is superb, I told him my vehicles symptoms..same as yours but with the temp gauge going up under load or at high speed, then falling to normal with heater on full.. straight away he said circulation problem without a doubt prob rad full of muck..two solutions, 1. take it off and try and get it properly and professionally flushed out or 2. buy a new one. Might do second option,lol. Hope yours is cured soon I know how frustrating it is.
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sparkymik
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Re: Cracked Cylinder Head - Negative

Post by sparkymik » Sat May 08, 2010 10:53 am

Hi I hope this helps I had a leak and it was the water pump, however it only leaked when hot and you need to be double jointed to find it as no water was evident under the Bongo it was evaporating off as it landed on the hot pully below the pump I found it at dark of night with a powerfull torch

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Re: Cracked Cylinder Head - Negative

Post by jaylee » Sat May 08, 2010 11:26 am

Water pump leak on mine too! But seemed to be evident when the engine had stopped??

I had a big service done to mine recently including a few new hoses.. Runs a lot cooler! :wink:
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chalky

Re: Cracked Cylinder Head - Negative

Post by chalky » Sat May 08, 2010 9:21 pm

Hi, thanks for the help.

I will check the water pump.....where is it exactly?

There is abserlutely no white smoke out the back, although the car does splutter about 15 seconds after starting. This has happened for a long time and happens every time when starting from cold. Temp guage never budges from 12 oclock, perhaps the darn thing gets stuck.

Pressure test has been done by the garage both times so I dont know if its been done hot. The real kicker is that one garage said they found trace gases in the coolant, while another found nothing. On the basis that the garage that found nothing wrong actually had it in to do the head for 1500GBP, I am enclined to believe them and really apreciated the honesty.

Does anyone have any tips when doing the UV test. I have ordered a standard UV bulb and the orange dye. My plan is to fix the lamp to a length of cable, wait till dark and start looking around underneath and into all the nooks and crannies when hot. I will have beforehand put the dye in the header tank and driven around for half an hour. Is this long enough, how far does one have to go before engine/cooling system is really hot and functional.

This may be a silly question, but if there is an internal leak in the engine, will any dye show up at the end of the exhaust pipe?. I suppose it would all burn off but would be quite conclussive.
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missfixit70
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Re: Cracked Cylinder Head - Negative

Post by missfixit70 » Sat May 08, 2010 9:41 pm

If the temp gauge is standard, it's pretty useless, it doesn't move once it's warmed up until it's already overheating basically. you can fit a Mason alarm or any temp sensor Haydn Callow sells a load as well as the Low coolant alarm, woth having a look at the factsheet in the members area on the various coolant alarms, there's a link to a mod you can do to make the temp gauge more sensible. There's also a factsheet on doing the waterpump (as well as one on overheating ,but some of the info is a bit iffy on that one IMO) or look on Lushprojects to see where it is - http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=34517.
It does sound like it could be the head gasket or worse, but check all the other options, did you pressure test the coolant system? I used this simple set up http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=38823 & it found about 5 weeps on hose connections (bloody silicon hoses :roll: ) that I thought were ok.
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Re: Cracked Cylinder Head - Negative

Post by wishmaster » Sat May 08, 2010 10:44 pm

If after checking and exhausting all other possibillities :? and still you cant find the problem, why dont you put a bottle of steel seal in and see how it goes :idea: . Do a search and you'll find some good info on here and judge for yourself. Some folk have had good results with this stuff :) Might be worth a go.
Good luck

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