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[Dave Coulson]

Hi,

This is a long story and will appreciate any comments / advice ..

Enfield Himalayan 2018 15000 miles
Location Mexico, small town no dealer near.

I adjusted the tappets , correct TDC etc , pretty sure all ok.

(The bike was running fine but could hear the top end tinkling , measured gaps , way too tight.)

I removed spark plug to double check piston piston height.

Crossed threads evident near top (changed this plug many times previously no problem). Damn!

Tightened in with a spanner to try and start the engine, one or two metal shards but removed using magnet from piston head as at tdc. Have ordered a back tap tool to fix better later so plug goes in with fingers. Am thinking of ordering a heli coil to fix permanently when remove head to do so, have spare gaskets to do this.

Tank removed several times to do tappets.

When I start , the revs race then die after five seconds, or if touch throttle.

Now battery is dead and have ordered a charger.

So,,,, in the meantime any ideas what I could do in the meantime...

Could it be a problem on the fuel supply, pump fires up.

Could it be the spark plug has gone in 'wrong' eg too tight, wrong angle...

Could it be shards of metal inside the engine, am thinking this not the reason and am intending to change the oil after running a few miles to be on the safe side.

I don't think I went anywhere near the idle screw.

Could it be a huge error adjusting the tappets?

Could it be that the battery didn't have enough charge to run the bike, only start it... unlikely?

What would you do/try next please

Cheers Dave

[Wheaters]

It might be an inlet side air leak.

[Dave Coulson]

Interesting - will investigate thanks

[Andy C]

Sounds like fuel starvation.

You say that you took the tank off - take a look and make sure that you have not pinched the breather tube that runs from the tank to the cannister under the frame, its easily done.

[Dave Coulson]

Will double check this Andy thanks

[Haggis]

The bike was running fine but could hear the top end tinkling , measured gaps , way too tight.)

If the gaps were too tight there would be less or no tinkling.
Also any thread material from the head would be aluminium and not magnetic.

You sure you checked and adjusted the tappets on the compression stroke?
Once you get your battery charged and make sure the charging system is working, battery should be around 14v with the engine running.

[Dave Coulson]

Hi thanks for the response,

Yes there was a high pitched tinkling sound, at high revs , am not sure now if the gap was less or more originally , it was less than spec at one point but repeated this a few times as tightening the lock nut kept moving the setting so was maybe more originally.

Am pretty sure was at correct TDC..

I rotated the crank anti clockwise until the T was in the inspection window. Then wiggled the valves and they were rock solid. Repeated and wiggled again and there was slight movement at the exhaust and very slight at the intake. And checked with a straw that the piston head was at the highest point.

Yes aluminium but the bits stuck to a magnetic screwdriver sure enough...odd but glad they did

14v sounds good but I don't have a volt meter with me unfortunately but can get one

[p]

Dave, it is difficult to give advice when you don't know the experience of the person asking, so sorry if I am stating the obvious, no offence intended!
You can use jump leads from another vehicle to test for/eliminate battery problem; as far as the metal fragments are concerned, if they are attracted by a magnet then they simply didn't come from the cylinder head.... are there any stripped thread on plug which I suppose may explain them??
If the top couple of threads were crossed, but you have managed to get plug in correctly then I wouldn't worry too much, there are plenty of good threads if the plug is turnable by hand and goes in smoothly once correctly started. I think there is a tendency for some to overtighten plug and stress threads, just a gentle nip is sufficient. A damaged plug will wreck head threads in double quick time though, so always check.
I would be inclined to double check that valves are indeed correct on compression stroke, there are of course two TDC's on a 4 stroke engine and timing marks show on both...... it's an easy mistake which could lead to your symptoms and explain tight valves if at "wrong" tdc. I sort of hope that this is the case, as it's easily rectified and you can be up and running without further ado......

[Dave Coulson]

Thanks for for the advice.

Yes I know what you mean re experience.
In brief, I have 'serviced' my own motorcycles for many years including this one but in a 'general' way including wheel bearings steering bearings etc and have experience of electrics.

However this is to the first time have adjusted valves although have experience of using feeler gauges for other purposes.

I have never completely dismantled an engine but have removed the top end on other bikes.

I am thinking now that the screwdriver had grease on it which the filings stuck to, definitely not from the plug, from the head, only one or two.

Am reassured that the plug is probably in straight and true , thanks.

(At some point will have to fix properly so can change it easily but will leave in place for now, it's screwed in with a wrench)

I will re do the valve clearances carefully and it is interesting that if they too tight would cause the symptoms, great news. I suspect that when tighten the lock nut it moves my settings and will triple check the gap is still as I adjusted it after tightening and at compression stroke.

(I am using .080 - .10 mm intake and .23-.25 mm exhaust as per various docs on the web)

Yes I could jump it if had leads but the charger will be here any day hopefully and fortunately am not heading further south for a while, am in a remote part of Chiapas Southern Mexico , next step Guatemala when conditions allow..which is why I am servicing as much as I can when have space and a bit of time and access to international post. I ordered pads, seals , filters, bearings etc from here and a tappets adjusting tool. Absolutely brilliant service , things get here within seven days and am in a remoter part of the country in the mountains.
No real problems on the road other than an oil leak from one of the 8mm engine bolts which just re-tightened.

Thanks again for your advice.

I will post on here what transpires

[Dave Coulson]

Just to elaborate on plug situation

I have attached a photo of the damaged plug threads.

I had to use a spanner to get the plug all the way down, it won't turn with fingers at all. The good news it will come out as turned wrench back an forth as went in.

Am hoping to fix the threads when the back tap tool arrives then later effect s permanent solution with a heli coil at some point.

It's unfortunate that this had happened at exactly the same time as adjusted valves ( took it out to check piston height) will leave alone until recheck valve clearances and test.