Engine swap

[Elingles01]

I read a few posts here but was hoping to hear from anyone that has positive or negative experiences of an engine swap (like for like) on a bongo. I bought an unconverted N-reg 2.5 diesel back in February. As soon as I bought it I had it pressure tested and a Hayden coolant alarm fitted by my local garage. It all seemed to run fine and we have had good use of it and a couple of lovely weekends away. A few weeks back my wife took it away for a weekend camping and it overheated and was brought back to London on the back of a flatbed.. This time I took it to a recommended Bongo garage in south London. The cylinder head was sent off, tested (failed) and skimmed and I've had a new radiator and water pump fitted. The issue is the mechanic can't get it to bleed and having worked on Bongo's for 15+ years, he's fairly sure there is an underlying problem possibly a crack in the engine. I've been through the old receipts that came with the van and it looks like it overheated back in September last year and that time round also had to have the cylinder head skimmed (according to my current garage pretty badly). The work that was done on it before all looks pretty shoddy with wrong bolts /nuts and clips missing and it may even had had the thermostat tampered with. The mechanic has suggested that it might be better to look at an engine swap rather than trying to take out / diagnose / fix the current engine block if it is cracked.

In summary it looks like a was probably sold a lemon and right now I'm trying to work out whether to cut my losses or try and fix it. So I was wondering if anyone had any experience of swapping an engine for a secondhand / reclaimed one. I was also wondering if there was anything else that maybe I should look into regarding not being able to bleed the system after it overheating and being put back together. As I say he's a recommended garage on the forum and says he's tried everything he knows to try and bleed it without success.

[roosmith]

There will be more technical people along in a bit to discuss this from that side but I would be wondering, if it is unconverted, is there anything else special about it, or is it a fairly standard, 10-a-penny Bongo?

You can probably see where I'm going with this but there has to be a point where it just isn't worth carrying on. If you'd had the Bongo years and had had extensive body work, drive train work etc you might want to stick with what you know and get it fixed or if you had thousands of pounds worth of conversion for instance. If this is still essentially a random Bongo with a broken engine (and a history of being patched up not fixed properly) perhaps it might be time to get another one that has been better looked after?

[Simon Jones]

Depends how handy you are with the spanners. A decent used engine can be picked up for about £650 and then if you factor in about £100 for new cambelt, oil, coolant, filters etc you could get it back on the road again. Sell the remains of the other engine for spares or scrap and you could very easily get much of your money back. I bought a spare engine with a cracked head and by selling the parts I've generated at least £200 which I've been able to put towards other things for the van.

[haydn callow]

You say it failed a pressure test....then was skimmed and replaced.....I would say from what you describe that the head is cracked around the exhaust ports and in fact a new head is what you need.
I would get it to a bongo savvy garage and get them to sort it....sounds as though the garage you used is not bongo savvy.

[Elingles01]

Thanks for the comments so far. Just to clarify the first time the head was skimmed (before I bought it) it looks like it was a fairly bad job. The company that skimmed it this time round say it wasn't level. Could a badly repaired head lead to a more serious problem such as a crack in the engine block ? Which could be why even though the head has been skimmed again properly, the system won't bleed ? Is there a way of actually testing the engine block itself without removing the engine ?

[haydn callow]

I still reckon the head is cracked.....

[Simon Jones]

I've only ever heard of one Bongo owner with a cracked block so you'd have to be pretty unlucky to have that happen. If the head itself is ok, then my guess is it's the way its been fitted. If you stick a perfectly flat head onto a 19 year old block which may have distorted it's not likely to seal perfectly. Two top tips given to me by a well known Bongo garage which I've used successfully (as have several other people on the forum) is to 'deck the block' (to help remove any imperfections in the mating surface) and use Wellseal compound on the new gasket to give it the best chance of making a reliable seal.

If it were me, I'd pop it all back together following those tips and see how it goes. Change the cambelt too as it should never be re-used.

Re: testing the head, did they do it warm or cold? Any cracks tend to become apparent when the head is hot and the alloy has expanded. If they tested it cold then it's not going to give a realistic result.

[francophile1947]

I still reckon the head is cracked.....

Indeed - skimming won't cure a cracked head, yet you say the Bongo specialist had it skimmed A crack may only appear once the engine is hot, so a cold engine may pass a short pressure test, but it will make it impossible to bleed the cooling system.

[Elingles01]

Thanks all i'll ask the garage to double check the head when they are back from holiday. A couple of points to clarify:

-I double checked the receipts from the previous owner and it looks like it had a broken head bolt (front left) that had stuck in the block and had to be removed, same time the head was skimmed last september.

- This time round (two weeks ago) the head was tested both cold and hot. It passed the cold test but failed the hot. I was told it was "repaired" which I assumed meant skimmed but could well be the wrong terminology.

- My mechanic also told me it looked like the thermostat had been tampered with or cut. All in all it had been put back together rather badly (last time round), so could have been bodged to sell on (to me....).

I'll ask to have the head checked again and see if there is anyway of salvaging this.

[haydn callow]

The broken bolt could have been the No 1 manifold stud......no need to remove head to fix that

[Simon Jones]

Be worth getting more info on whereabouts on the head the problem was and how they repaired it.

[teenmal]

What caused the engine to overheat? . Was it lack of coolant if so did she get a warning from the low coolant alarm?.

Re bleeding you could Ask the mechanic to drain the cooling system, flush the system, remove the temperature gauge sender,( top o/s front of the cylinder head), fill header tank , wait until the coolant flows from the cylinder head then refit sender.


I think your Mechanic will understand this procedure.

PS They could also use a Vacuum kit.


Good luck.

[David Edwards]

I gave up on my original engine when the garage trying to fix it, ruined it, lol I bought an engine from george at bongospares, absolutely superb, was delivered within 2 days wrapped up like a giant brick on a pallett, had loads of stuff still on it too and runs like a dream, the new garage fitting it..diesel specialists..said they had never seen such a good second hand one, it was as it came out of the donor car as well,no washing of any bits to hide leaks etc. Well worth a ring to ask george how much, lol..07836 598528.