Head gasket replaced; no start/run V6

[williefixit]

In May this year, I put my V6 into a Bongo specialist and Bongo-friendly garage to cure an oil leak. They replaced the camshaft seals and all was fine until it leaked again a couple of weeks ago. This time the same garage diagnosed a leaking head gasket and has replaced both, with heads being skimmed etc.

The problem is that the engine won’t start and they don’t really know why. I think we can assume that spark and fuel are present and the problem is more subtle.

They suspect the oil has been lost from the hydraulic lifters (hydraulic tappets) and have ordered a full set (24) as a bit of a trial, but don’t know if they will come with oil in them?

Whilst I know the principles, I’m no way an expert with engines and can’t understand why these tappets need replacing, as apart from the oil leak, the engine was running beautifully before the work was commenced.

If anyone can suggest what the problem might be, I will pass the suggestion on to the garage.

Thanks.

[Titan1995]

All hydraulic tappets/lifters that I have experienced need to be soaked in oil prior to installation. Even then expect some rough running for a moment or two once installed.

Totally unfamiliar with the V6 petrol engine though.

Hope you have some luck on this one.

[Simon Jones]

My thoughts would be either the timing of the camshafts is wrong, lack of spark, or incorrect sequence of HT leads. Have they tried a compression test? That may shed some light on what the valves are doing.

[Titan1995]

Even with totally wrong set up with HT leads one would expect the engine to fire albeit not run.

Find compression on #01 cylinder and work your way around the firing order from there.

[mikeWalsall]

Seems a bit hit 'n miss with a professional garage not knowing what's wrong and 'maybe' fitting 24 new tappets @ £70 each 'just in case' ..

[Titan1995]

Seems a bit hit 'n miss with a professional garage not knowing what's wrong and 'maybe' fitting 24 new tappets @ £70 each 'just in case' ..

I totally agree......basic principles of compression, fuel and a spark. Even with incorrect valve timing would get a bang or two.

One assumes that that you cannot get the valve timing out by a huge margin without causing fouling and associated damage.

Sadly, I have never played with the V6 petrol but I am sure that there are many on here that have.

[teenmal]

In May this year, I put my V6 into a Bongo specialist and Bongo-friendly garage to cure an oil leak. They replaced the camshaft seals and all was fine until it leaked again a couple of weeks ago. This time the same garage diagnosed a leaking head gasket and has replaced both, with heads being skimmed etc.

The problem is that the engine won’t start and they don’t really know why. I think we can assume that spark and fuel are present and the problem is more subtle.

They suspect the oil has been lost from the hydraulic lifters (hydraulic tappets) and have ordered a full set (24) as a bit of a trial, but don’t know if they will come with oil in them?
Whilst I know the principles, I’m no way an expert with engines and can’t understand why these tappets need replacing, as apart from the oil leak, the engine was running beautifully before the work was commenced.

If anyone can suggest what the problem might be, I will pass the suggestion on to the garage.

Thanks.

Hi, this seems like a very expensive trial Will they absorb the cost of the HLA s (Hydraulic Lash Adjusters)if they dont cure the problem?
The HLAs at times need to be primed/bled.

Cheers.

[williefixit]

Thanks for all suggestions to date. I know the garage is looking at them.

Some guys in work who are familiar with hydraulic tappets on other engines suggested a few problems associated with possible poor oil supply to the tappets. (Some of the suggestions may not be possible - they are not familiar with the Bongo):-

Wrong gasket - holes in gasket don't line up with oil ways.
Gasket upside down, reversed or out of line - holes in gasket don't line up with oil ways.
Debris from skimming - blocking oil ways.


Discussed with garage and they say oil galleries OK.

[steveyd]

Hi,

I have no experience specifically on the Bongo petrol engines but I do know on lots other types things like cam position sensors, crankshaft position sensors can go wrong- the ECU needs a signal from these and if it finds none it will never fire the ignition. If the heads have been off it could well be a single missing connection/socket-- or just needs a new sensor - try giving it a wiggle (refer to manual as to where it is/if it has one).

Just a thought.. my sisters Corsa had the same issue...and was cheaply and easily fixed. Also I wouldnt have thought poor hydraulic lifters would prevent the engine from starting - it would sound like a bag of nails but at least it should go!

cheers,

Steve

[Titan1995]

Hi,


Just a thought.. my sisters Corsa had the same issue...and was cheaply and easily fixed. Also I wouldnt have thought poor hydraulic lifters would prevent the engine from starting - it would sound like a bag of nails but at least it should go!

cheers,

Steve

My thoughts exactly Steve. I worked at GM dealers for a number of years and that was always the case with the hydraulic lifters. That is why one would keep them in a bath of oil prior to fitment.

[williefixit]

Forgive me for taking so long to post this, but I don’t like to think about it.

However for the benefit of others who may find this discussion in the future, I can report that after the installation of 24 new hydraulic tappets (from Japan) the Bongo is running well and we had it back before Christmas, after a stay of 9 weeks with the Bongo specialist.

[mikeonb4c]

Forgive me for taking so long to post this, but I don’t like to think about it.

However for the benefit of others who may find this discussion in the future, I can report that after the installation of 24 new hydraulic tappets (from Japan) the Bongo is running well and we had it back before Christmas, after a stay of 9 weeks with the Bongo specialist.

Phew! I was getting quite worried for you.

[teenmal]

Hi williefixit,glad you got it fixed.If you dont mind me asking,what was the cost of replacing the 24 adjusters.

Thanks.

[williefixit]

I can’t really say how much it cost to replace them, as the installation cost was part of the main head gasket work and my total bill took account of how long the Bongo had been with the specialist etc. However the parts cost per hydraulic tappet as fitted was £40.69 ex VAT. I did get a quote for non-Mazda parts @ £8.45 incl VAT. The supplier said they were to o.e. spec, but I didn’t interfere with what the specialist had ordered. I understand that the specialist is going to include for these in any future V6 heads they carry out. (i.e. will include the cost of them in any quote and get them in stock before commencing work)

[mikeWalsall]

£49 for an hydraulic 'tappet' is still better than the generally quoted price of £70 each ..

Did they replace the 24 or just the suspect ones ..??