1GM10 checking

Sniper

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I want to check the compression on my engine. Is the sort of gauge that I can buy at Halfords likely to be suitable? I seem to remember that these are held against the 'hole' (presumably injector site) while the engine is cranked.

On a related subject, I plan to clean out the fuel supply system this Winter. What is the best solution for the replacement pipes, which are currently copper? Also, I will need to dispose of about 4 gallons of old diesel. Do most local authorities have an arrangement for this?

Many thanks in advance for advice
 
Horatio

I haven't seen the Halfords compression tester myself, but most of them are of the same principle. Usually a cone (tapered) shape rubber grommet which you keep pushed onto an aperture, either spark plug hole in terms of ignition combustion engines and injector location hole for combustion ignition engines.
They will give you a compression reading, but they don't tell you much more.
Good compression figures don't always mean the engine is in good condition, they can be useful on multi cylinder engines to compare one cylinder with the other. But of course not in your case with one cylinder.

Why do you need to replace the fuel supply lines? I was not aware there is anything wrong with copper pipes for fuel feed, is there something I don't know? The component in the system to look at first would be the fuel tank. If it hasn't or cannot be cleaned, there will be a lot of sediment lying in the bottom. The next area to look at will be components which in the supply line which are restrictions. The internals of a fuel shut off tap can be quite clogged, due to the restrictions, bends etc.

If you haven't got a primary fuel filter with a sediment bowl, its worth investing in one. A visible glass sediment bowl will tell you a lot about the fuels condition.

I do believe there will be a oil disposal point at your local authority refuse tip. I usually get rid of mine at a marina, most of them have oil disposal drop off points.

Hope I have been of some help, good luck with your maintenance.

Ken
 
Thanks for the response Ken. The reason why I am considering replacing the fuel pipes is that I am assuming they may be quite contaminated. Copper has been fine, so presumably it is worth replacing like with like? I will, of course, try to clean the tank although it has no inspection port.

As far as compression testing goes, I am aware that a single reading won't tell me a great deal unless the compression is good and within the manfacturers specification. If its poor then I will be looking at either valves, rings or both.

The specific problem I am having is poor starting. Once running the engine is fine, which is hopeful. For this reason I think dirty fuel may be the main problem. I am planning on replacing the existing primary filter for a new one.
 
I want to check the compression on my engine. Is the sort of gauge that I can buy at Halfords likely to be suitable? I seem to remember that these are held against the 'hole' (presumably injector site) while the engine is cranked.

On a related subject, I plan to clean out the fuel supply system this Winter. What is the best solution for the replacement pipes, which are currently copper? Also, I will need to dispose of about 4 gallons of old diesel. Do most local authorities have an arrangement for this?

Many thanks in advance for advice
The push in compression gauges that you get from Halfords and the like WILL NOT give you an accurate reading of the compression of your diesel engine.

Firstly the compression is off the scale of the typical petrol type compression tester that is described.

Secondly, you are unlikely to hold it in the injector hole by hand against the compression that a good diesel engine produces.

You need a diesel engine compression tester - and they bolt or screw in place!
 
Horatio

Poor cylinder compression can be a cause of poor starting. So can badly adjusted valve clearances.

Can I just add that fuel itself doesn't clog or cause a coating build up inside fuel lines. It would be small solid particles, such as rust and the dreaded fuel bacteria, which can restrict fuel lines. It wouldn't affect a straight run in the pipe, it would be a connection, adaptor, "T" piece or 90 deg bend that would collect suspended particles. Or as previously stated, a fuel shut of tap with its associated adaptors to be favourite for collecting the suspended nasties.

Don't forget the fuel lift pump, it can get clogged as well.
 
Thanks again for the responses. I'll bear those in mind when I start to work through the fuel system. Ken - you mention the fuel lift pump. Do you by any chance know if the 1GM10 has any sort of membrane in the pump that might degrade, or am I on the wrong track here?

John - thanks for the info about diesel compression gauges. I had a feeling that might be the case.
 
Horatio

The fuel lift pump has a diaphragm (like a membrane), it can eventually stretch or deform a little. But it wouldn't normally cause poor starting as the injection pump should stayed charged with fuel, enough for initial firing it up. Unless the lift pump is in really bad condition it could cause ingress of air. Air getting into the fuel system can be a major cause of poor starting.

Ken
 
Unless you have evidence that the fuel lines are contaminated then that may be a red herring. The exhaust elbow commonly fills up with carbon deposits, that can cause poor starting. This year mine had a new exhaust elbow and tappets adusted which transformed the starting.
 
The local authority sites I've seen exclude diesel from recycling. But then, an odd gallon ....and they don't check.
 
Getting rid of the old fuel.

Our local authority tip has a tank for used engine oil. As long as you don;t make it too obvious you are pouring gallons and gallons of fuel in one go you should be able to use that to dispose of old dirty fuel. I suspect most LA tips are the same. Sorry, did I say tip? I meant "recycling centre!"
 
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