Club 80-90 Forums

Evening all.

Over the last few trips, the van has developed a really poor idle. Once off of the choke, intermittently the revs drop to approx 500 ish, and it's barely ticking over.
At this point, the engine rocks in the engine bay.

It doesn't always do this though, but another symptom is stalling at lights when slowing from speed sometimes.


I thought I would start with basics first, and thought perhaps air leak. Used the carb cleaner to check for increasing revs while it was running rough - no bueno.

Today I went with dizzy cap, rotor arm, leads and plugs.
Started with cap, leads and arm - no bueno. Issue remained despite the arm having clear scorch marks on it.

Here's the kicker.... Took out the plugs to change, and they are all sooty.... Very sooty.
No oil, just black hard build up on all 4. The weird thing is, they are labeled as R6 Bosch, not the WR7 DC+ I have found others comment on via forum searches, and the ones BW send out.

So the question is; what vehicles are these plugs used for ( if any VW camper ) and could they be causing weak spark to enable carbon build up?

I've changed the plugs for new WR7 DC+ and it runs nice. Going to have to go for a drive tomorrow to see for sure as symptoms are intermittent.

My thoughts are, if the plugs are not issue, or others here feel not likely, then I am more inclined to think there is another underlying issue that will result in same symptoms eventually returning.

Pics below - let me know thoughts:



 

Are the R6 plugs made in Russia?

maxstu wrote: ↑05 Apr 2023, 18:46 Are the R6 plug made in Russia?

Unknown Stuart.
They were Bosch if that means anything.

 

What was the gap of the old plugs?

Smiffo wrote: ↑05 Apr 2023, 18:47

maxstu wrote: ↑05 Apr 2023, 18:46 Are the R6 plug made in Russia?

Unknown Stuart.
They were Bosch if that means anything.

 

It should be written on the waist below the socket facets.

tobydog wrote: ↑05 Apr 2023, 19:20 What was the gap of the old plugs?

About 0.8mm for all of them.
Although, that includes copious amounts of black deposits 

maxstu wrote: ↑05 Apr 2023, 19:33

Smiffo wrote: ↑05 Apr 2023, 18:47

maxstu wrote: ↑05 Apr 2023, 18:46 Are the R6 plug made in Russia?

Unknown Stuart.
They were Bosch if that means anything.

It should be written on the waist below the socket facets.

Well, well, well.

They are Russian. What does that indicate do you think?
 

They're crap!
I had exactly the same issues with a previous van. Including deposits on the side of the rotor.

I have a run down to Cornwall this weekend.
Think I will leave as is now, ( assuming it's all sunbeams and rainbows on my trial run tomorrow ) then check the plugs again when I return home after the weekend.

If they are going black again, I know there is something wrong.
If not, I'm going to add this to the list of things we can blame Putin for 

How old are they? I bought some a few years ago and they lasted about 3k. I reckon it's their poor heat range that causes the problem. French made Bosch work well.
Certainly check gap on new plugs before running down to Cornwall.

They were from last MOT ( which was December. ) I'm going to guess under 3k done since then for sure.

I've got the new Brickwerk supplied WR7 DC+ variants in it now, but trying to do this between work stuff left me with a trial run to do tomorrow. It didn't repeat the poor idle on the drive, but to be fair, it doesn't always do it.

30mins up and down the motorway tomorrow will bring the gremlin back if it isn't cured now.

Gap on new plugs is 0.7mm

Well.

Just went out for a 45min run. All seems good so far.
Plan is to run for a couple of hundred miles, then recheck the plugs. If they are going black again, I know something else is wrong.

( Changed air filter too as precautionary task on the off chance it was restricting airflow and causing carbon build up on the plugs if fuel/air ratio was being impacted. ) 

Time will tell.
 

OK....

So, the gremlin returned. Very rough idle, revs drop to near stalling, and if approaching a junction, sometimes it did stall.
Went with coil next time.... Drove the van around, and after a while, it reared its ugly head once more...

These darn intermittent issues are a pain!

Anyway - I tried to do a carb rebuild yesterday, and as I spilt the two halves, a piece of metal falls out and I was present with this:



One of the tabs that holds the float in place has cracked off.

Long story short, with only the TCI(?) module left electrically, I started leaning toward fuelling issues. Fuel is pumping out nice, so I opened Pierburg's magic Voodoo box 

Despite not knowing if this cracked tab is actually the issue, I could only conclude that it wasn't good. I went to my box of job lot bits and started looking through the carb bits I had.

Between the top halves, one had a working choke flap intact. I went through the pulldown units, and attached the ones that appeared to be working. The top half was from a later carb and my faulty example was early, but the base looked like it would mate OK with the later top half, so I went with it....

Used some gaskets from an old Brickwerks kit I had and had never used, and gave the whole thing copious amounts of carb cleaner, wire bristles in jets, cleaned out the best conical filer I had etc, then re-assembled.

Now I have no idea if this will work. I just went for a 15min run on residential streets and up and down the local main road and it seems to be running sweeter than it has for a long time - I hadn't realised how poor it had been running over the last few months. 

Now for the ultimate test..... Will the intermittent poor idle issue return?

I will let you know over the next few days 

 

Right....

A tad under 100 miles later, and I am chuffed to bits so far.
Still don't know if the later top half of the carb, mated to an early lower half is going to cause issues, but it's the best I have so I am running with it 

Another 100miles or so, and as long as idle issues are resolved, I will check the plugs again to ensure no soot.

See you on the other side!!

Oh, we do like a happy ending.