Locating a possible minor oil leak - advice needed

mikeonb4c · Post by **mikeonb4c** » Mon Mar 12, 2007 11:07 pm

When I inspected my Bongo prior to purchase I noticed the block was a bit oily. It seemed that this might originate from the rocker cover gasket area. Possibly it was old. There was no obvious sign of serious leaking or spillage.

When working on the Bongo yesterday, I noticed oil (engine oil I think) on the block, more or less behind the fuel injector. Just to confuse things, I noticed (and had noticed on one occasion before a couple of months back when I cut the engine whilst running it at 2500rpm) a little diesel fuel falling from the injector area.

The long and short of it is that, although I dont think I have a serious problem, I would like to find out if the oil is freshly leaking (you'd think it would be drying by now if it was an old leak, now stopped) and if so, and provided it isnt v difficult and not worth the effort, take remedial action. Yesterday, I did tighten a few of the rocker cover nuts on the side opposite the fuel injector (there was a line, maybe old, of oil around there) as they didnt seem tight. I didnt tighten them much though as I recall years ago that tightening them unevenly could distort the rocker cover and worsen a leak (mind you that was pressed steel on BMC engines and we used Red Hermetite back then!). So:

1) Is the first action to apply Gunk with a brush and wash it off to get the engine clean, or might that have undesirable side effects like de-greasing components, and causing the cab to smell of Gunk forevermore. ANyone done this exercise?

2) Is it to be expected that some Bongo engines may weep a little oil

3) Do fuel pump/injectors drop a little fuel when engine running nhard and stopped suddenly or should ther never be fuel leaks (are we looking at worn O rings if so)

I'd welcome any thoughts and advice in this area & thanks as ever chums

Mike

ebygum32 · Post by **ebygum32** » Mon Mar 12, 2007 11:23 pm

dude

be careful when you tighten the rocker box bolts as the bolts tend to sheer being soft bolts i am gonna order a rockerbox gasket from either place on ebay for £10 or mazdabongo.com whichever cheaper and get a set of high tensile bolts, mine has just started to leak on the passanger side near the back of the engine, the job itself should not be that hard to do poss one hour as got to strip the same stuff off as when you change the glow plugs just to get to the box will keep you informed but wont be done till i'm back home next tuesday

haydn callow · Post by **haydn callow** » Mon Mar 12, 2007 11:27 pm

Is it under the drivers seat at the top front of the engine? is it black mucky stuff ? On mine, when I was in Allans Vehicle Services last week in Plymouth, he told me it was to do with a silicone gasket weeping and was very common. Nothing to worry about and although unsightly not a problem unless the leak is bad.

francophile1947 · Post by **francophile1947** » Mon Mar 12, 2007 11:28 pm

Aaah!! the smell of Gunk on a hot engine! - the motorists Chanel No. 5

1) I would use the Gunk. Until it's clean, you can't see where it's leaking and the beautiful aroma does eventually go.
2) As long as it is only a seep, and you can't easily fix it, I wouldn't be too worried. Different matter if it's bad enough to require frequent oil top-ups.
3) Sorry - dunno the answer to that.

haydn callow · Post by **haydn callow** » Mon Mar 12, 2007 11:29 pm

Should never be any fuel leaks. Would also be a way in for air.

mikeonb4c · Post by **mikeonb4c** » Mon Mar 12, 2007 11:49 pm

Fantastic set of replies chums - and so quick. Must be a favourite evening hobby for all of us. Cold beer and chat on BF. V interested to hear how you get on ebygum and thanks for the warning. Ironically, I was probably saved because my old memory of BMC rocker covers made me wary of over tightening, for the wrong reason, but with the right result

I'm dying to use a bit of Gunk franco - its been so long. The family will just have to be educated to it.

I think the fuel leak problem is minor, but I will cue it up as a job to do at some point (if I dont get fed up to the back teeth !!). Waddy reckon people, worn O rings or some such?

pyroman · Post by **pyroman** » Tue Mar 13, 2007 2:06 pm

Hi mikeonb4c,

i had a similar leak from my fuel injection pump, it was an 'o' ring that had perished. Hard to get to but you can fix it yourself and save a lot of dosh.

mikeonb4c · Post by **mikeonb4c** » Tue Mar 13, 2007 5:58 pm

I remember reading that thread pyro - I'll try and dig it up and re-read it. Did you find your symptoms similar to mine i.e.

1) Dripping (not always, but maybe when fuel pressure head might be higher - not that I understand all this!).

2) Wetness on the engine block. It could be that I'm looking at fresh diesel mixed with an old oil incident si that I get hte impression of an engine oil leak when in fact it is down to diesel leakage

Grateful for any insights. I'll try and take a pic and post it on this thread. Right now though, I dont think it is serious - just nice to get it sorted at some point to get the Bongo in tip-top condition - and I think I need a break from sticking my head under the f*******g bonnet, much as I love my Bongo

MattK · Post by **MattK** » Tue Mar 13, 2007 7:43 pm

Mike,

I had a similar problem that took a while to find. I thought I had a serious problem as black liquid would collect around near the position of the head gasket.

It turned out to be a slight leak from the rocker cover gasket (GENTLE tweak of the bolts cured this one) and also a small leak from the fuel pump that was cured by (I think) replacing a washer.

Engine now long term shiny!!

celt and kaz · Post by **celt and kaz** » Tue Mar 13, 2007 7:44 pm

The diesel leak could also be split or hardened spil pipes. Those are the little rubber looking pipes linking the injectors. As you said mike, the diesel mixing with previous oil sat on the engine could actually make it look worse than it is.
If it is the spil pipes, they are easy to replace, just buy yourself a length of pipe from an auto factors, make sure it is spil pipe, and simply pull of each pipe in turn, cut required length of new pipe and push new pipe back on. The end injector will probably have a rubber nipple on one of the spil tubes. If that is split they can also be purchased from an auto factor.

mikeonb4c · Post by **mikeonb4c** » Tue Mar 13, 2007 10:51 pm

Turning into an excellent thread this. What a Club. Thanks everyone for all the advice above. Plenty to think about. I'm actually enjoying IMPROVING the Bongo by tackling these jobs, rather than waiting until they have to be done. Get a tremendous shot in the arm for my confidence each time I tackle one of these jobs and get to reap the benefit afterwards. There is no way I could have afforded to have it all done. Great therapy for me with some recent job problems etc. I've had + I get an A1 Bongo at the end of it.

Will I ever get my life back, that's the big question.

pyroman · Post by **pyroman** » Wed Mar 14, 2007 8:34 pm

Hi Mike,

Yes the leak was from the pump and I did get "wet" patch on engine which was due to fuel dripping onto engine block.

Happy Camper · Post by **Happy Camper** » Sun Apr 01, 2007 8:52 pm

Does this look like a rocker cover gasket leak?

Harry · Post by **Harry** » Sun Apr 01, 2007 9:39 pm

Well if it is I've got one too and have had since a year last August when I bought it, over 100,000 km ago...don't think it can be serious.

Incidentally I had my last oil change 60,000Km (1 year) ago and have only 'topped up with 1 litre twice.

Didn't know about regular oil changes..but its getting changed this month on its annual service!

cheers

H

mikeonb4c · Post by **mikeonb4c** » Sun Apr 01, 2007 10:10 pm

Looks like it Happy Camper. But as Harry says, it aint no big deal - Brit motorbikes were always like this (except on a Sunday afternoon when their owner had just given them a good gunking and went out for a ride to show off). I'll clean mine up at some point just to see if it is still active and maybe tweak those rocker cover bolts - but be careful, see warning earlier on in this thread - if it is the cause. Too busy getting ready for summer just now

Locating a possible minor oil leak - advice needed

Locating a possible minor oil leak - advice needed

Oil Leak?