Bongo Fury

This received from Victoria who lives in the South of France.

For the last four months I've had a small amount of white smoke on start up with Bongo which I never had before. In last four weeks I've noticed loss of power somewhat up hill and gurgling of air/something going back into coolant reservoir after a long run when the engine is hot.

There is a small oil leak out of gasket area around no 1 cylinder, possibly coming out of the no 1 spark plug. It's not a great leak in general but it is there, and it wasn't two months ago.

I've just driven 1200 km down to France, and went out for a drive in the mountains on Monday, and on way back, on quite heavy braking in rain, engine revs were trying to drop as if brake vacuum was being lost below normal 850 revs on idle.

Battery is new, and engine always run smooth on idle. Vacuum hoses, brake discs and pads all seem OK but it feels like the vacuum and power seems to be trying to drop out. I got it home but going up hill it tried to stutter a couple of times, I drove it slow, I don't think the issue is electrical. Could it be the head gasket? I've not had any overheating problems.

Any words of wisdom or advice for Victoria?

is the plug tight

I am led to believe the 2 litre is self bleeding & may have an addtional pipe that feeds into the expansion tank. A long run up the mountains is going to result in coolant running very hot so some bubbling in the tank sounds normal especially if there is the extra pipe feeding any air back into the system.

Unless the coolant is being over pressurised and forced out the overflow, or there is any signs of oil/coolant mixing, I wouldn't put head or gasket issues top of my list. If performance is down, I would start with the 3 things you needs to make it run:

- Fuel. Has the petrol filter been changed recently? Try running on some premium unleaded petrol for a couple of tanks. Try some fuel system/injector cleaner.

- Air. Has the air filter been changed recently? Check inside the filter box and pipework for any debris or obtructions.

- Ignition. Have the plugs been changed recently? Check the HT leads are in good condition which fit snuggly on their connections & there are no cracks or damage to the insulation. Clean off the oil around the spark plug as that can encourage problems. Try running the engine at night & watch for any signs of tracking where the high voltage is arcing from the leads. It may also be worth checking / changing the distributor cap & rotor arm as well as the HT leads if they are looking tired.

You mention heavy rain was a factor. That could also point to a problem with tracking on the ignition system resulting in a loss of power.

In summary, start with the simple, relatively inexpensive service items which will need changing at some point sooner or later, and then see how it goes. I think you may find it will improve matters.

I would go for a Compression Test before you start chucking money at it for unnecessary parts.

HI, the replies listed here prompted me to check spark plugs, rotor cap and arm, ht leads ,air filter and oil leak again. No 4 spark plug was slightly loose,(the one with the oil coming out), I cleaned up all four(all a year old) and tightened them all up a bit more. Air filter less than a year old was clean. Nothing seems to be jamming air lines. No 4 ht lead has cracked at the bottom bell,and the distributor cap looked tired, so I ordered new ones up of these. Fuel filter should not be an issue its been changed twice in the last 12 months. Went for an hours spin on flat roads at quiet pace. After leaving to cool, checked the plugs and oil leak under passenger seat again. Oil leak had returned ,very small, could be coming out of rocker cover or head, can't tell until further inspection. All plugs absoleutly clean. It started to rain. Went for short run of 20 minutes. Fine for first half, then slight stuttering again on reversing out of parking. Sounds a bit like missing timing to me now. Also on finish, air in coolant had returned,(after a bleed),maybe exhaust gas? Pressure of coolant had seemed okay.Rain may be an issue.
Engine vaccum seems to try to drop upon braking, is this back pressure causing this.
Thermostat will be changed tomorrow,and coolant again. All belts seem okay. Will do a compression test back in England but do not have timing guns etc here with me now.
I don't want to use the steel seal, and am will wait to see if new cap and leads does the job.
Thanks to all replies, very sound advice not to rush in and think it's always the gasket on a Bongo,
Regards, Victoria. chez Bongo. (en France) (will provide an update if any useful information emerges)