checking tappet clearances

[bobngo]

bought my first bongo about a month ago,2.5 TW engine, been just about everywhere on this site , as a result have changed the air filter, blanked off the EGR valve, changed all the brake discs and pads, changed the whole exhaust pipe, changed the oil in the engine and auto gearbox, phew its begining to come up to scratch now.

but i have a strong tapping/thumping noise somewhere around number one cylinder, which gets louder as the load on the engine increases, i think its a tappet abit slack, but theres the problem, to get to the tappets the gear change lever , brake lever and top cover have to be removed, in order to remove the camshaft cover.
anyone any ideas or experience of this ??? i can,t find anything on the site that covers this

or is there something else in that area which could cause the noise ???

for many years i was a R.A.F engine fitter, worked on just about everything they had ,so not afraid to delve deep into engines, but this is my bongo and any help /advice would be good

thanks in anticipation

bobngo

[francophile1947]

If my memory is correct, it's only 4 bolts holding the top cover in place - the levers move out of the way with it I did it once to make replacing the glow plugs easier.

[missfixit70]

Quick search on "Tappets", here's one of the topics - http://www.igmaynard.co.uk/bongo/forum/ ... ts#p302261 If you go for it, take piccies & do a bit of a write up if you can, may help others

[bobngo]

thx francohile and missfixit for the quick reply.

looking at that top cover seems an awful lot of bolts ,any idea which four it might be ???

can,t believe it would need all of them taken out

[missfixit70]

The instructions for doing the cambelt in the factsheets in the members area should help with that.

[dandywarhol]

There's more than 4, about 10 bolts from memory, fairly straightforward. If the noise increases under load then I don't think it's a tappet - which is worrying Under load noise usually means a lower end/crank area problem.

Maybe you've got a dribbling injector causing a bit of extra "delay" time causing the noise...............

[stevedon]

its about 8-10 10mm head bolts and 2 12mm for the hand brake and 2x12mm for the gear shift and just lift the cover away.
the tappets are easy just remember 3 valves per cylinder
inlet 0.1mm
exhaust 0.2mm
the knocking noise could aslo be an injector whos spray pattern has gone from a mist to a squrt,this will make the same noise

[bobngo]

thanks everyone for your help, i think it might be easier to change the injector first, before taking it apart to adjust tappets.
definitely comeing from the number one cylinder area

just hope its not a bottom end problem

[thedogsbollox]

thanks everyone for your help, i think it might be easier to change the injector first, before taking it apart to adjust tappets.
definitely comeing from the number one cylinder area

just hope its not a bottom end problem

I would suggest removing all the injectors and getting them tested. I remember when i was working on plant diesels we had a pump to test injectors. Screw on the injector and press the lever and see what pressure it released at. You could also see if there was a squirt or a spray.

[rita]

thanks everyone for your help, i think it might be easier to change the injector first, before taking it apart to adjust tappets.
definitely comeing from the number one cylinder area

just hope its not a bottom end problem

Hi,
if you take out No1 injector and swap it with No4 injector the noise should transfer to No4 cylinder.

This should prove your injectors.

[bigdaddycain]

thanks everyone for your help, i think it might be easier to change the injector first, before taking it apart to adjust tappets.
definitely comeing from the number one cylinder area

just hope its not a bottom end problem

Hi,
if you take out No1 injector and swap it with No4 injector the noise should transfer to No4 cylinder.

This should prove your injectors.

I like your thinking!

[thedogsbollox]

Good call

[bobngo]

dogsbollox, that brilliant thinking, that going to be my first move.

thx alot , why ca,nt i think like that, lateral thinking or as they say now thinking outside the box

then if the noise does not move ,i,ll try tappets, and just hope its not something in the bottom end !!! although japanese engine are not normally noted for having bottom end problems , !!

[bobngo]

just had a thought , i do,nt have any experience of diesel engines, if i should need new injectors, do these come from the factory ready set up, or do they have to be set up on the vehicle after fitting ,
or put another way does anything have to be adjusted ???? or is it just out with the old and on with the new ????

[mikeonb4c]

just had a thought , i do,nt have any experience of diesel engines, if i should need new injectors, do these come from the factory ready set up, or do they have to be set up on the vehicle after fitting ,
or put another way does anything have to be adjusted ???? or is it just out with the old and on with the new ????

You're right to be cautious with this I think. If Dandywarhol doesn't come on here and offer advice then try PMing him as he is top dog on serious Bongo mechanics. You don't want to mess with the injector stuff and wreck it. I'm no techie but I've read posts about how its a fiddly piece of kit - expensive to replace too if things go t*ts up.

I agree with you that bottom end trouble is out of character for these engines, which seem to be robust in that respect