Engine Compression Tester

[Arceye]

Hi does anyone have any suggestions for an engine compression tester make or kit?
My little 3 cyl JCB 403 smokes like a steam train, not sure if it's rings or valve seals.
I can easily put it in the heater plug hole to test.
Loads on ebay/amazon etc in varying quality and prices, I'm not likely to be using it daily!
Thanks

 

[Swarfmonkey]

I've used Lang and OTC compression testers in the past. Both did the job fine, but unfortunately rather pricey. A leak down test (sadly, another bit of kit to buy), can help narrow down problems before you start tearing things apart.

 

[box]

If you're only buying it for one job on one machine, get the cheapest diesel engine compression tester kit you can. They're about 60 bucks down here. They last if you look after them, they're accurate enough for comparison between cylinders.

A leak down tester is easily made with an air fitting, a bit of pipe and an old glow plug.

 

[JD6920s]

Hi does anyone have any suggestions for an engine compression tester make or kit?
My little 3 cyl JCB 403 smokes like a steam train, not sure if it's rings or valve seals.
I can easily put it in the heater plug hole to test.
Loads on ebay/amazon etc in varying quality and prices, I'm not likely to be using it daily!
Thanks

Do you know a mechanic with one , better to bung him a good drink for an accurate reading than a cheap eBay guestamate as he will have a decent one. Might be the injectors anyway, how many hours, and how does it start?

 

[Magnus Oyke]

You can get used Sykes Pickvant compression testers and all sorts of other stuff on ebay for half resonable money. You could probably use it and sell it on again for what you paid less fees

 

[Arceye]

Done 4000 hours, starts reasonable, just runs smokey.
There was egr on it and for a long time it always felt like it had a smokers cough, it would stutter a bit then wheeze and eventually choke itself to death(apologies to smokers).
When in bits I disconnected the egr and put the head breather pipe to the exhaust outlet. Valves looked absolutely filthy and coked up, cleaned them up but they need to be done properly.
Head gasket wasn't gone completely but some leakage somewhere since one cylinder had a brown deposit on it.
Had a crankshaft bearing slip around and seize the engine. I put in a new one and it runs ok.
When the head was off I could see no scoring on the liners or pistons.
So I'm thinking it needs the head and valves cleaning, possibly skimming and new seals. This is easily done but time consuming.
I want to check if the piston rings are worn since this will mean engine out and complete strip down to do.
Gets used every day on feeding cattle so I can't go long without it.
If I can say it's piston rings or valve seals or both I will know which way to go with it.

 

[box]

Has it got a turbo?

 

[Arceye]

non turbo

 

[DrWazzock]

I found pressurising each cylinder at a time with my air compressor was a starting point with valves closed obviously. You could hear/ feel air rushing out of a dodgy valve or past leaky rings.
Surprised though that an engine is that bad at only 4000 hours. I’d look at the state of the injectors first and make sure all the easy stuff is in order.

 

[Arceye]

No1 290 psi, No2 420 psi and No3 440 psi.
No 1 smoke belches out from the heater plug hole, no smoke from the other two(fuel off of course)

 

[thesilentone]

No1 290 psi, No2 420 psi and No3 440 psi.
No 1 smoke belches out from the heater plug hole, no smoke from the other two(fuel off of course)

Looks like the smoke in unburned fuel from No 1.

At least you know where to go first.