SUBARU SUMO carb problem **please help**

[paulhills]

Hi everyone, I am hoping someone may be able to offer some help on a carb issue I am having. I have a 1991 1.0ltr subaru sumo (uk model) EF10 2WD 5 speed, manual choke, which developed (im guessing) a gearbox issue. I had the van loaded (moving house) on the motorway when it started to vibrate quite dramatically (particularly the gear lever. When I dipped the clutch it would settle down, but as soon as I engaged the gears it would vibrate. At slow speed it was ok, but after 25-30mph it would start to vibrate again (so I guessed clutch or gearbox). When I took the gearbox off I couldn’t see anything really wrong with it (I didn’t open it up, but there was no play with the gearbox, clutch seemed fine and the flywheel didn’t show any signs of wear / warping). I had a spare engine I bought off ebay (the guy said it was rebuilt a couple of thousand miles ago and then sat for 1-2 years). The oil looked good and the crank moved freely and it looked like a very clean engine. So I swapped the engines over, fired it up and it idled and revved fine. I timed it up and it was running fine, responsive and sounded great.

I thought it would be a good idear to flush the water through the engine as it had been sat without any water running through it for at least 2 years. Unfortunately I snapped the bolt in the inlet manifold for the thermostat housing. As I had a spare manifold from the engine I just removed I swapped them over (to save drilling out the snapped stud). Fired the engine up and 100metres down the road the carb started playing up. Now it will not idle without the choke pulled halfway out and half throttle. If I go full throttle it cuts out (too rich I think). I cleaned the carb out .. still the same. I swapped the carb for the one off the other engine… still the same. I thought maybe the inlet manifold was leaking air, so I took it off and re attached with fresh gaskets and paste,.. still the same. I have played with the mixture / idle / tried without the airfilter attached and it still will not idle without choke and throttle and cuts out whenever you try to rev it up.

I thought maybe the solenoid was causing an issue. So I removed the solenoid valve and covered the hole. Now it would start and idle without the choke, but touch the throttle and it will cut out. As it was idling I tried spraying a mist of wd40 around the carb / manifold to see if it was sucking in air anywhere, but nothing… I don’t know what to try next! Any suggestions would be greatly appreciated
Thanks, Paul

[fupabox]

after everything you've tried I would hazard a guess at possibly the fuel filter...when you removed the fuel lines from the old engine the fuel backwashed through the filter into the tank (like removing your finger from th end of a full drinking straw)....maybe once started it sucked in enough clean fuel to run for a bit ,then sucked up the backwashed crud...just a guess

[paulhills]

thanks for the quick response fupabox!
i think the fuel is reaching the carb ok ( i took the fuel line off of the carb and turned the ignition on and fuel shot out of the pipe). tonight i will check the filter and take the top off the carb to see if any crap has ended up in the float chamber,.. and maybe drain the fuel tank and put fresh fuel in case whilst i am at it.

[Krieger-san]

Quick question: salvage yards don't keep Liberos in the UK? From what I saw on TV and stuff, the UK is a car enthusiast heaven with lots of breakers yards selling all kinds of parts?
Try finding a replacement unit. How 'bout companies that rebuild them?

[paulhills]

drained and replaced the fuel and unfortunately no improvement :-(

Hi Krieger, unfortunately the liberos (sumo's in the uk) are quite rare now. Since i bought mine 3 years ago, i regularly check ebay / autotrader and have only seen 5-6 for sale (half of which were for spares or repairs). also 2nd hand parts in the uk are becoming hard to find. 3-4 years ago the uk had a scrapage scheme (buy a new car / van and the government would fund £1000 towards it if you part ex an old vehicle -by law all the part ex cars/ vans had to be crushed). this was to try to reduce the co2 emmissions in accordance to EU regulations. this was further incentivised with the introduction of low emission zones in london and other major towns, where it would cost up to £100 a day to enter with a vehicle that didnt meet the emission requirements! also the price of metal has increased which means there are loads of adverts from companies saying they will take scrap vehicles in any condition for free or even pay you for them if they are large vehicles (to weigh in for recycle metal)

[Krieger-san]

Bummer, dude. I feel your pain. A similar program is run by our government. You trade your old car(I think it has to be at least 12 years old or something like that), and they give you a voucher for 800 euros that you can use when you purchase a new car. You can also trade in multiple cars for multiple vouchers and you can give/sell the voucher.
Tons of awesome classic(or less classic, but still effin' sweet) cars got massacred during this program. I know for a fact that one Libero(in full working condition) got scrapped. It was listed on an automotive forum and I wanted to buy it, but I didn't had the cash and it was from another city. Later on I found out that the owner decided to trade it in for a voucher because no one wanted to buy it.
Also, we have bigger registration taxes for older cars. I still have to sort that out, I need to get the van working before I go and do all the paperwork.
Listen, I can't give you any advice on how to fix your carb(I'm clueless myself), but I have some pics of the Repair Manual and there's something about the manual choke carb. If you want, I can send you those pics. It's in German, but you can try and work with that.
Cheers!

[paulhills]

think i have solved my carb problem! although i am not 100% sure what i did! :-) i took the carb off, took it apart and cleaned it again with carb cleaner and a air line.as i was taking the solenoid off the insulation where the cable attaches to it cracked open, so i cut it off and resoldered the cable on and replaced everything. fired it up and it was running alot better. adjusted the throttle and mix and its been running fine since! :-) if anyone else experiences the same problem i would suggest checking the cable to the solenoid first (easier than attacking the carb) also make sure that the solenoid cable is connected dorrectly to the wiring loom (i noticed that the electrical pin in the connector is offset, so you have to make sure you line the two cables connectors up correctly when pushing them together - i hope that makes sense). if that doesnt work, clean the carb thoroughly and hopefully it will cure the problem!

[Krieger-san]

Congrats!
I'm really glad you got it fixed. Please upload some cold start videos, some pics, stuff like that. I would really love to see/hear your Libero run :) .