Winget PH1 starting problem

[willie.macleod]

Hi Julian,

I'm getting the figures from here for compression:

http://www.oldengine.org/members/diesel/PetterData/PetterPH2.htm

also says compression ratio should be 16.5:1 - do these sound right? the compression tester I used went from 0-1000 psi so I thought 535 psi sounded a reasonable enough pressure for a diesel, the 200 psi I was getting would be good for a petrol and enough that I could feel compression when hand cranking, just not enough to get the diesel to combust?

Unfortunately the nuts aren't standard, they are half hex and half round (the round part sits against the head instead of a washer-not sure what they are called) - I suppose I could use standard nuts and washers though.

Image0046.jpg

I think I gave the wrong impression when I said the head gasket was leaking, it is actually blown in one section so will have to splash out on a new one. Will speak with John Lewis Dumpers on Monday. Thanks again for your help.

[Julian]

Hi Julian,

I'm getting the figures from here for compression:

http://www.oldengine.org/members/diesel/PetterData/PetterPH2.htm

also says compression ratio should be 16.5:1 - do these sound right? the compression tester I used went from 0-1000 psi so I thought 535 psi sounded a reasonable enough pressure for a diesel, the 200 psi I was getting would be good for a petrol and enough that I could feel compression when hand cranking, just not enough to get the diesel to combust?

Unfortunately the nuts aren't standard, they are half hex and half round (the round part sits against the head instead of a washer-not sure what they are called) - I suppose I could use standard nuts and washers though.


I think I gave the wrong impression when I said the head gasket was leaking, it is actually blown in one section so will have to splash out on a new one. Will speak with John Lewis Dumpers on Monday. Thanks again for your help.

Right 16.5:1 is a good figure for a diesel, add up 16.5 atmospheres (say 15psi for convenience) and you get 247psi. Obviously that's a good figure. 535psi is a typo.

Yes a new head gasket required. I'm recommending you pop over to http://www.stationary-engine.net/forum/ They will be much better at directing you towards spares suppliers. Also Peter Forbes (the chap who's site you quoted), is the main man over there and is a font of knowledge on these small diesels

Julian.

[Jeremy Rowland]

Willie the blown head gasket would definately make the engine hard to start, I would personally recommend that you make sure the head is still flat where it has been blowing by using a straight edge and trying feeler gauges under it, I would also take the trouble to check that the valves are seating correctly before putting the head back on.
To check the head for flatness you first need to simply clean off any excess carbon and rust with some emery cloth and use a small feeler gauge under a decent straight edge.
It is important to check that the valves and seats are okay because whats the point in repairing the head gasket if the compression gases are simply bypassing the valve seats as well as the blown head gasket?

Jeremy

[FOWLER MAN]

Hi Willie,
I have many years experience on these engines so I'll poke my nose in here and hopefully I can be some help.
Firstly i'd like to say the PH is very reliable and easy to maintain. They start very easily if correctly set up, I have known them start without the decompressor by just pulling them over one compression when warm.
Critical to geting this sort of starting ease are getting the bump clearance and injection timing right.
The bump clearance (Piston to head clearance) is set by adding or removing shims from between the crank case and cylinder barrel. These shims are provided as part of the head gasket set, and the clearance is 36 to 42 thou."
It can be set by placing a peice of lead wire or soft solder on the piston crown (away from the valves) and fitting and tightening down the head with the new gasket in place.Turn the engine over then remove the head. Using a micrometer measure the thickness of the wire. It should be 36 to 42 thou." add or remove shims to acheive this.
If you can't get head nuts you should be OK with standard UNF nuts and collars or washers.
Spill timing the pump is not too difficult. There are two marks on the flywheel 24 and 28 deg., turn the engine on the compression stroke till the mark lines up with the pointer on the crank case. Check the plate on the head, it should give the governed speed, up to 1650 RPM use the 24 deg. mark. over 1650 RPM. use the 28 deg mark.
Remove the four bolts from the side plate below the pump, there will be a tappet type adjustment in there to time the pump.
Remove the delivery union from the top of the injector pump and carefully remove the delivery valve plunger and spring. (keep clean and safe for refitting). Refit the union witout the spring and plunger.
Fuel will flow from the union.
With the 24 or 28 deg. mark lined up ,adjust the tappet till the fuel just stops flowing. Blow fuel from the union orifice as you do this to help determine the precise cut off point,(a spill tube is reccomended but not essential).
Lock up the tappet at this point and replace all components.
Compression pressure is 535 psi. at running speeds but will be much less when cranked by hand.
You should not need easy start but if you do use it watch the engine does not kick back, it could break your thumb or wrist.
There is nothing wrong with using ether based starting aids, in fact Petter reccomended it for their AA & AB series engines.
If the engine proves difficult on first start introduce a little oil through the inlet manifold, but dont over do it. This is better than using easy start. It doesn't kick back!!
Engine oil is SAE 20, starting will be more difficult with a heavier oil.
I beleive gasket sets for these engines are still readily available.
If I can be further help dont hesitate to PM me, I'll give you my number and we can talk.
Fred.

P.S.On some PH engines there are two sets of 24 / 28 Deg. marks to facilitate the setup for reverse rotation running. If there are two sets on your engine, make sure the ones you use are lining up just before TDC on the compression stroke.

[Jeremy Rowland]

Thanks Fred glad you've had the experience on them I can only offer advice based on my own experiences with larger engines.
I would still check the head for flatness though and the valve seating as a matter of precaution, I gather from what you have said that the piston to head clearance is critical so any leakage of compressed gas would result in much harder starting problems hence the blown head gasket would cause this problem.

Jeremy

[Julian]

Indeed. Though it's probably worth noting that bump clearance and spill timing, albeit important settings, are probably a little spurious in this context. I'd say they are set by the manufacturer or engine overhaul shop and probably not likely to change in service.

All we need here is a new head gasket, (in the first instance) we don't need the rocket science yet

Julian.

[FOWLER MAN]

Indeed. Though it's probably worth noting that bump clearance and spill timing, albeit important settings, are probably a little spurious in this context. I'd say they are set by the manufacturer or engine overhaul shop and probably not likely to change in service.

All we need here is a new head gasket, (in the first instance) we don't need the rocket science yet

Julian.

Yes Julian, you may well be right, the above settings may be OK, but in my experience with long service engines it's worth checking.
A pot and piston may have been changed in the field just re-using the original shims.
As the pots and pistons vary you cannot assume the clearance will be correct. It only takes at most, an extra quarter hour to check when replacing the head.
The pump may have been replaced, probably without checking the spill timing and whilst it will still run reasonably well, for the sake of half an hour this too is worth checking.
Naturaly I had assumed from Willies thorough aproach to the job that the basics would be put in order first.
As a matter of interest there are a number of engines which require particular attention to "Bump Clearance" for instance many Listers use steel shims under the head, some of the big Ruston engines had three peice con-rods and introduced shims into the rod itself to adjust it's length and raise or lower the piston in the bore. Another which comes to mind is the Perkins P series where we had to install the pistons, measure the piston height individualy then turn down the crowns in a lathe, typicaly in a P6 that might vary from zero to 60 thou. no two pistons being the same. These could hammer the head if not checked.
Not rocket sience, just part of the job.
Fred

[willie.macleod]

Thanks all for the info - especially Fred for all that detail! much appreciated. I like the sounds of starting on one turn. I think I gave it a lifetimes worth of turns so far so I reckon it owes me any easy life after this

At the moment I have ordered a head set from Geoff Quick at e-gaskets (£12 delivered), it is hopefully in the post just now. Took the head into my local diesel shop and they are going to clean it up for me in their parts washer, check it is still flat, check the valves are sealing OK and give me a new set of BSF nuts and washers. For £20 that sounds good to me, think they have a soft spot for little diesels, the crankshaft I saw standing beside the bench I left the head on was the same height as me

Next thing will be to find someone locally who I can borrow a micrometer from which is easier said than done, I've got some plumbing solder I could use which should squash nicely.

What is the recommended way to torque the head nuts? There is no room for a torque wrench, I take it this is done as closely as possible to the recommended 60lb/ft by feel?

On a side note - I'm also trying to get this dumper to stop - the drums refuse to come off the hubs, they seem well stuck on, I can't see any obvious holes to put a bolt through to drive them off, hitting them with a hammer hasn't worked (yet), does anyone have any tricks for getting drums off?

Thanks again for the help given!

[Julian]

does anyone have any tricks for getting drums off?

Thanks again for the help given!

I used a propane blow torch to heat mine up and calibrated beating with a copper hammer! (not too hard) You need a proper blowtorch, not one of those daft little things from B&Q. Mine came off at a temperature that was just starting to affect the paint on the drum.

Julian.

[FOWLER MAN]

does anyone have any tricks for getting drums off?

Thanks again for the help given!

Can't add to what Julian has said, the drums can be very tight. If you fail you could remove the nut and pull the hub flange and drum together with a standard hub puller attatched by the wheel nuts.
Your right about the head nuts, good ring spanner and good judgement. For many years Gardner engines provided a head spanner with instructions,"as tight as possible with this spanner".
One tip for later, if you do check the bump clearance cut two peices of solder about 6 mm. long and stick them to the piston with a bit of grease. Stick them as near over the gudgeon pin as possible,one each side, (missing all the holes).
Good luck.
Fred