Bad running GS1000E

[Suzuki mad]

The story so far.

Got rust in the fuel system on my 1981 GS1000E after a NOS suzuki fuel tap change went wrong. (I forgot to filter the fuel going into the tank.) Bike dropped a cylinder so put it off the road for a few months. Stripped the carbs off, replaced intake rubbers and 'O' rings, had two screws drilled out and replaced with bolts. Carbs cleaned not fully to the instructions, the blocked jet found and sorted. Rebuilt it all but the engine still ran bad. Fuel pipe was leaking then broke apparantley making the bike run lean. Changed pipe that seemed to sort it.

Went for her first ride today, only got about 2 miles when she dropped a cylinder (no2) and I nursed her home on the other 3. Now I've got an oil weep from the head gasket between No2 and No3 at the back of the engine. Looks like its trying to bubble through the gasket. So looks like I've blown a head gasket now.

So, is this still a carb problem, a head gasket problem or both? Is it a result of the carb problem that the heads gone?

Looks like I will have to strip and rebuild the carbs fully as per the manual and do the head gasket at the same time. Not what I wanted with the 1000S project coming next week.

Suzuki mad

[Suzuki mad]

Spoken to Suzuki dealer in the UK and they don't do the seals on the link tubes or air screws. Where do you guy's get your seals from. Please remember that I'm in the UK not the USA.

SB.

[trippivot]

rust is a problem that does not go away. you can drain the bowls often and gravity will get the particles out but not all of them

acid etch and seal the tank first. new filters hoses and such down the line to the carbs .

finally after a millon hours and a million carb on - off apaart reassemble
float height adjustments jet cleaning etc.. you'll get a smooth ride

dont forget to remove all the float needle seats and flush the bodies out too it is an important detail. that stuff packs up behind the needle and seat way inside and is tough to get to. even before the junk gets to the jets

keep tools under the seat and drain the dead cylinder float bowl and that might help next time on a test ride

[trippivot]

the oil in the area between 2-3 at the head surface is the camchain galley where oil runs with the chain it is a high splash area not a compression sealing area.

fix the fuel delivery system and just clean of the offending oil for now

[Suzuki mad]

This afternoon, out came the carbs, on the bench. Stripped No2 and no signs of rust or anything. Loads of fuel in the bowl so, move on.

Decided to move the air jet which I hadn't done. All 4 were black and a dark mixture was coming out of the ports. Cleaned that up and gave it a blow through with the airline.

Took out the air screws all were set at 2 1/4 turns from seated. All were dirty on the point end. Blew some air in and out popped a load more of this black mixture from the air jet and the small hole inside the carbs by the butterflies.

Fitted new vacuum and fuel pipe (just cos I had some spare.)

Re-assembled the carbs to the bike and fitted the air box and tank. Stuck it on prime and after a short turn over way she went on all 4. Brought the tickover up on the group screw under the carbs and she settled back down to 1,200 rpm. Now's she's running as a GS should.

The morale of this story.
1/ Do the carb strip as per the instructions.
2/ Don't put rust into your tank from another tank/bowser.
3/ Don't rush the job.
4/ Change all the parts that you can get.
4/ Always ask questions as you sometimes don't know all the answers.

Thanks GS resource members.

Suzuki mad.

[Big T]

Spoken to Suzuki dealer in the UK and they don't do the seals on the link tubes or air screws. Where do you guy's get your seals from. Please remember that I'm in the UK not the USA.

SB.

If you're talking about O ring seals in the carbs, try cycleorings.com. Robert's a member here and he stands behind his product. I'm sure he'll ship to you.

[seuadr]

This afternoon, out came the carbs, on the bench. Stripped No2 and no signs of rust or anything. Loads of fuel in the bowl so, move on.

Decided to move the air jet which I hadn't done. All 4 were black and a dark mixture was coming out of the ports. Cleaned that up and gave it a blow through with the airline.

Took out the air screws all were set at 2 1/4 turns from seated. All were dirty on the point end. Blew some air in and out popped a load more of this black mixture from the air jet and the small hole inside the carbs by the butterflies.

Fitted new vacuum and fuel pipe (just cos I had some spare.)

Re-assembled the carbs to the bike and fitted the air box and tank. Stuck it on prime and after a short turn over way she went on all 4. Brought the tickover up on the group screw under the carbs and she settled back down to 1,200 rpm. Now's she's running as a GS should.

The morale of this story.
1/ Do the carb strip as per the instructions.
2/ Don't put rust into your tank from another tank/bowser.
3/ Don't rush the job.
4/ Change all the parts that you can get.
4/ Always ask questions as you sometimes don't know all the answers.

Thanks GS resource members.

Suzuki mad.

i second that. pilot idle circuits get forgotten alot unfortunatly.

[SqDancerLynn1]

Many time trying to take shortcuts you end up doing the job twice

[Suzuki mad]

OK. I do give up for the day.

Seems to be running sweet at tickover and you take her out for a run and she keeps dropping down onto 3 cylinders.

I pulled the plugs leads off and when I get to no 2 there is no appreciatable change to the tickover or running of the bike. So was my carb problem always an ignition problem.

Well, I've swapped over the plug caps with a spare set, thats not worked. I get a fair old jolt from the cable to No 2 when I am holding it. You can see sparks through my bike gloves in the daylight. None of the other plugs do the same. Could it be my HT leads have finally broken down?

I will put a new set of plugs in tomorrow just to check and get some new plug caps but i think I am wasting my money on this. What do you guys recon.

I don't have any electrical testers here (I don't even know what to buy I've always been a mechanical engineer.)

Suzuki mad

[seuadr]

just a simple volt/amp and resistance multimeter should be ok. it may be a coil issue, try swapping 1/4 and 2/3 and see if it is still the same cylinder that is dropping.

[Suzuki mad]

Swapped 2 and 3, over no change.

I've just pulled the plugs and No2 is wet and black, not oily but black. Looks like its not firing or struggling to fire. I will try new plugs in the morning and get a basic multimeter also. Lets hope the Suzuki manual shows how to test this sort of thing. :-(

Suzuki mad

[hampshirehog]

Just a thought, and I'm having brain fade here, you could have a dodgy tap and the vac line is sucking petrol into the carb hence massively rich. (Brain fade because I can't remember which carb the vac line is attached to).
Sorted my mate's NC29 a fortnight ago - same symptoms and this was the cause. Test by sticking the tap to prime and blocking off the vac tube.

[Suzuki mad]

Up and at it again this morning. Check No2 plug and there was no spark at all. Tried another plug and there was spark so looks like I have a 'duff' plug. Swapped plugs and she run on all 4. Going to take her out again and see if she drops the cylinder again.

If she does what do you guys recon?

Suzuki mad