Techenders, 11th - 13th June 2021. Who's There...?...

Well, I think there was an element of maybe leannness on @paulcalf's engine but also the fact that a 2110 on 3 cylinders runs like a 1600... So it got cooked at some time and then the valve seat kept falling out and resetting. We just found it at TE because I was asked to check the cranking current using my 2000Amp clamp probe meter on an oscilloscope (like Krypton engine analysers back in the 1980s , and I could see one cylinder draw 180 amps , two drew about 160 amps, and one drew 110 amps, with a low point of 100 amps between pulses. So I knew there was uneven compression - for instance my engine just produces a marching set of almost identical current pulses.
We could hear chuffing from the right hand side, and whistles and chirps. So we worked round the engine with a "proper" compression tester and got 115psi on No1, maybe 10psi on No2. So at that point we knew it was likely bad cylinder, probably valves as the breathers werent spewing oil, and the engine wasnt using oil..
Checked with valves rocking and the clearance on No2 exhaust was massive . Took the rockers off and checked again, and No2 exhaust was down quite a bit. Thats just a tommy bar across the valves and poking around with a phone.



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My loop of shame - I drove hard down the A34 as far as Chievely Services where I stopped for a coffee and a pastie as I was starting to feel a bit tired.

I got the cylinder head to 130C and the oil to 115C which is hotter than it has been for over a year. And then I stopped the bus.

But the bus didnt make it out of the services first time quite as intended -:



A while back I decided to re-use an electronic ignition module that had gone funny at the end of a motorway run on the commute to work. I discovered also a short from the choke wire on the progressive to the fan housing, which caused intermittent ignition symptoms similar to a faulty module. So I didnt outright condemn the module.

Since then I havent driven it hard, but while hammering down the A34 at between 65 and 70mph on the flat, things got hotter ..

And when I stopped the distributor stopped being cooled by the airflow in the engine bay and warmed up to the oil temperature. And at 115 degrees C, the module decided to let me drive it out of the car park at the services and then just stop in the middle of the exit road. I was able to wind the bus off the road using the starter, with occasional blips of power from the engine , and park it on the entrance to the filling station.

The distributor and the clamp nut on the stud on the engine block were really too hot to hold. Swapping hands repeatedlyI got it off the engine and the spare in place, swapping the distributor cap over , but noting the rotor arm position before and after to speed up the alignment of the dog in the drive.

But the clamp had been too loose and the timing was off. I did a crude static timing while in the middle of the filling station entrance , then got the engine going using a remote starter wire I permanently fitted and hid as a data cable going to the computer.

Then I drove right round the services, back into the car park. Did the timing properly , painted a mark on the pulley because that had worn off, tightened everything properly, finished my coffee, had a chat with somebody who used to own a Purple Devon who was parked next to me in his average black car, got back on the road, and decided I liked the advance curve of the "new" distributor better.

A half hour delay, no panic, the services were really quiet. Must have been the footie.

It starts to make me interested in electronic units, where the temperature sensitive bit is not stuck on top of the engine. (the pulse timer for shutting off current with no pulses from the Hall effect transducer in the module).
Not a 123 because that is expensive, and it leaves the electronics in a very hot place.

 

Arrived home after an uneventful journey unlike Mike, thanks to all for great company, banter and general madness. Hope @paulcalf manages to source a head in the morning, safe trip back to Edinburgh for @F_Pantos and hope you're all feeling a lot better @scrooge95

 

Is it? For some reason I’ve got it on the calendar as the 28th! So that’s 3,4,5 Sept! Better dates! Off to mess up the calendar!

 

Ozziedog,,,,,,,Yes Mike.

 

Your stories are always an interesting read

 

Thanks all for a great weekend, many thanks to all that helped with my carbs and engine running, thanks to @mikedjames for advice on my solar panels.

 

Just almost packed up for the long trek North, waiting to see what Paul's plans are, before I finally leave.

It's been a very welcome break away, amongst a universally friendly bunch.

My thanks to everyone who helped with the roof, very much appreciated, you all know who you are.


PS. If anyone else has stopped here when it's not the TE nights, it's an amazing spot, but without you lot around the road noise is really LOUD.

 

Glad you got back OK Mike.

Thanks for diagnosing my issue and potentially saving me from needing a new engine!

 

Did you get sorted Paul or are you still on site?

 

I'm sat here in the shade awaiting the RAC to get me back to Sheffield.

Spoke to the bloke who built my engine who gave the same possible causes as @zedders & @mikedjames gave.

Once engine is out I'll know if the head can be repaired or needs replacing.

@SundialCamperSpecialists to the rescue. Thanks very much.

I also need to find & address the cause of the issue eg blocked jet, air leak etc etc.

Thanks for the supportive messages. I'll keep you posted.

 

Do I read Mike's post right - that you hadn't noticed anything wrong and it was pure chance he spotted it while checking your cranking current?
Top job @mikedjames

 

No worries
I hope your feeling a bit better today

 

That’s right
Paul thought there was something up with the starter motor

 

Yes I thought it hadn't been starting with as much balls as usual, so Mike checked starter motor cranking.

His magic machine showed there was unequal compression when turning over.

Then spark plugs out & proper compression check showed number 1 at 120psi, but number 2 had 10 or 20psi!

Valve cover and rocker came off indicating the issue on exhaust valve.

Checked compression on the other 2 cylinders the next day, which are also fine.

Big thanks also to @areksilverfish & @Cockers who were assisting

 

Thinking back the past couple of times I drove the van it didn't feel quite right (bit lumpy) at first, but felt fine after 10 - 20 ish mins.

So when warmed up perhaps the valve seat moved/knocked back into place & then it was probably running on all 4 cylinders.

It was still climbing hills on the motorway with no apparent difficulty on the way to techenders.