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Engine trouble

Posted: 18 Jul 2015, 19:25
by Margo88
Hi, I am new to this forum and also new to t25 ownership. I have recently bought a 1988 1.9 dg water cooled petrol t25.
The van starts fine and drives lovely from cold. As soon as it warms up it starts playing up. Symptoms are engine stalls, lose of power under load. You can depress the throttle and ... Nothing. The van restarts ok when it stalls but runs very lumpy. It is fitted with a weber carb. My initial thoughts were a blockage or partial blockage in the Jets. I have cleaned the carb out, can't see or hear any air leaks but the symptoms remain. I have noticed slight burn marks on the inside of the distributor cap and on the rotor arm. Could this cause these symptoms?

Hope to get some replies from some knowledgeably people! Other than this engine trouble, I have well and truly caught the t25 bug!!

Re: Engine trouble

Posted: 18 Jul 2015, 20:00
by itchyfeet
Hot engine trouble can be coil breaking down.

Dizzy caps are not expensive, just replace it if in doubt.

Re: Engine trouble

Posted: 18 Jul 2015, 20:07
by Margo88
Thanks. Yeah. Someone must've retro fitted the weber at some point. I've got new dizzy cap and rotor arm on order. Will fit Monday. Doesn't smell of fuel. I believe it is automatic choke. I think the choke is the plate on the top of the carb (visible when the air filter is off). This is partially closed when cold and opens when hot. Do you know the correct procedure for checking the coil?

Re: Engine trouble

Posted: 18 Jul 2015, 20:42
by itchyfeet
You can test the coil resistance but if it's hot then it's probably faulty.
Primary 0.5 to 0.8 ohms
Green sticker 2.4 to 3.5 k ohms secondary
Grey coil 6.9 to 8.5k ohms secondary

Image

Re: Engine trouble

Posted: 18 Jul 2015, 20:47
by Margo88
Thanks very much. I'll test it tomorrow.

Re: Engine trouble

Posted: 19 Jul 2015, 07:27
by itchyfeet
Measure insulation also ( shown in diagram) it should be very high or open loop on meter.
Also worth cleaning up earths on engine head and under coil.

My guess is more likely ignition than fuel

Re: Engine trouble

Posted: 19 Jul 2015, 08:22
by Margo88
Morning. Just checked the coil. Primary and secondary resistance ok. Insulation 1 - 1.5 mega ohm. This is low. Do you suggest replacing coil?

Re: Engine trouble

Posted: 19 Jul 2015, 08:53
by itchyfeet
Thing is they break down hot (cold can measure OK) so give it a drive until it cuts out, open the hatch and see if the coil is hot to touch.

Re: Engine trouble

Posted: 19 Jul 2015, 13:27
by Margo88
Hi. Coil was ok. I took the carb off and cleaned it ... Properly this time! Just gone for a test drive. Engine up to temp ... No stalling or hesitation. Smooth power through the Rev range so hopefully she is cured! Thanks for your advice.