Suzuki Club UK

Last night after a very normal off roading session my '91 SJ 413 Samurai developed a problem... It will rev fine but as soon as you let the throttle off it dies immediatly! It will not run under 2k rpm! If i put the choke on it would idle high but very lumpy! I thought it was the idle jet in the Weber carb so I stripped it and blasted every jet with carb cleaner and then put it all back together. It fired up and ran fine for about 20 mins absolutely fine (except for an advance issue in the dizzy but that shouldn't affect it too much) then developed the same problem as before! It is almost undriveable as it only really runs right if i rev the hell out of it!

Has anyone else had a similar problem? Any help will be very welcome!

Thanks guys!
Ben

ben_moto501 wrote:Last night after a very normal off roading session my '91 SJ 413 Samurai developed a problem... It will rev fine but as soon as you let the throttle off it dies immediatly! It will not run under 2k rpm! If i put the choke on it would idle high but very lumpy! I thought it was the idle jet in the Weber carb so I stripped it and blasted every jet with carb cleaner and then put it all back together. It fired up and ran fine for about 20 mins absolutely fine (except for an advance issue in the dizzy but that shouldn't affect it too much) then developed the same problem as before! It is almost undriveable as it only really runs right if i rev the hell out of it!

Has anyone else had a similar problem? Any help will be very welcome!

Thanks guys!
Ben

Ben

It sounds like you put your finger on it first time around by stripping the carb and cleaning the jets which allowed the engine to run normally for a while. It's probably a dirt or water contamination issue and the running of the engine for 20 mins has dragged the next wave of foreign bodies through the pipework to repeat the situation. I would strip and clean the carb again, get a new fuel filter and fit it as close to the carb as possible to hopefully trap any dirt held between the tank and the carb. Hopefully this will cure the problem but in the end it may be necessary to strip the whole system down and thoroughly clean it. Also I would replace the standard fuel filter fitted near the driver's side rear wheel.

Ian

Thanks mate, I gave the car a full service about a month ago but one thing I didn't do was the fuel filter! I knew it was around the rear wheel but I couldn't actually find it! Would it be ok to just leave it and put an inline filter just before the fuel pump? or would it be better even closer to the carb? or should I track it down and replace the standard one? I'll try to get around my mates sometime this week and use an airline on the carb, I think that will get rid of any other rubbish in there!
The other problem I mentioned briefly was the my ignition advance vacuum diaphragm has ruptured, I have the Denso dizzy and it looks like it is a replaceable part on the side of the dizzy itself, can anyone confirm this? Where can I get this part from?

Thanks again for the advice!

Ben

once youve replaced the filter,, if it still does it.. start the engine and hold it on a rev range were it dosnt cut out. then spray some wd40 around the base of the carb and manifold. if the revs pick up,, you have a leak somwhere. i had the same proplem on a metro years ago, it turned out to be a manifold gasket cracked.

I was already planning on putting new gaskets on so that should't be too much of a problem! I would also like to know if anyone can tell me if the Weber carb is standard? I've read lots about asian carbs and on flea'bay I have seen SU and Weber carb upgrades?? Or is this particular Weber standard?
Thanks once again!

Ben

nope webers aren't standard, aisin carbs are the standard carb and most people think SUs are the best carb to fit because they are so basic and cope with angles well!

Scott

ben_moto501 wrote:Thanks mate, I gave the car a full service about a month ago but one thing I didn't do was the fuel filter! I knew it was around the rear wheel but I couldn't actually find it! Would it be ok to just leave it and put an inline filter just before the fuel pump? or would it be better even closer to the carb? or should I track it down and replace the standard one? I'll try to get around my mates sometime this week and use an airline on the carb, I think that will get rid of any other rubbish in there!
The other problem I mentioned briefly was the my ignition advance vacuum diaphragm has ruptured, I have the Denso dizzy and it looks like it is a replaceable part on the side of the dizzy itself, can anyone confirm this? Where can I get this part from?

Thanks again for the advice!

Ben

Ben

I can't answer the bit about the diaphragm as I run an SJ410 and this doesn't have one - some years ago I did own a Samurai and had terrible fuel contamination problems. I did replace the standard fuel filter and fitted an extra one in the engine compartment but this second one caused problems as well - what I'm suggesting is that you fit the engine compartment one to cleanse the fuel which lies between the standard filter and the carb to ensure that any contamination between the two is caught - having satisfied yourself that this is now clean, I would then remove it. Regarding not being able to find the standard fuel filter, it's fitted under or near the RHR wheel arch - it may be mounted on the chassis or on the inside face of it. I bought my fuel filters off Ebay for £0.99 plus postage.

Hope this helps

Ian

ihad the same syptoms, i replaced the filter, and magic, problems sorted, the fuel filter gets clogged up and starvs your engine, you might find these useful, I have a webber carb fitted to my SJ





Luke

Inside the float chamber is a diaphragm if its got a split in it this can cause the same problem.

I went to my mates today and stripped the carb again, but this time instead of just using carb cleaner I used compressed air as well! Fired up first time and runs like a dream now! Sorted! I am still going to change the fuel filter when I can find it!
Thanks for all the help and thanks for that breakdown picture of the Weber carb... It's exactly what I've got!

Ben