14 replies to this topic

[Mini-Hazel-Nut]

My word if it`s not one thing it`s another. This time I need the help of a Weber minded Mini type. Last week I did a practice session in the hot rod, drove up to my trailer ramp whereupon the engine died and refused to start. Last night I went to the practice track again but the Mini never left the trailer. I spent an hour trying to start it but best result was a chug chug with the help of the starter motor but no pick up. I checked the plugs several times but they were never even damp. I have checked flow to the float chambers today and there is no issue there. However there is apparently no fuel getting beyond that to the engine. Does anyone have any idea what is causing this and how I can rectify it please? The 4 jets under the top cap seem fine. Thanks all. 

 

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[nicklouse]

remove all jets and tubes and clean them out.

[Dusky]

I'd try starting without the jet cover on first. You can also pour some fuel in the jet cover to rule out a stuck float/bad pump.
If it starts without the jet cover your fuel breather is blocked.

[Mini-Hazel-Nut]

I was hoping you wouldn`t say that, lol. I`ve only just had it tuned (£100) and now I gotta disturb it all.

[cal844]

I was hoping you wouldn`t say that, lol. I`ve only just had it tuned (£100) and now I gotta disturb it all.

Take it back to the tuner say your having issues but don't want to disturb it

[nicklouse]

stripping it will not change anything the only adjustable parts are the idle screws.

 

my guess is the accelerator pump stuck.

[Mini-Hazel-Nut]

stripping it will not change anything the only adjustable parts are the idle screws.

 

my guess is the accelerator pump stuck.

While I had the top off I depressed and released the pump and it seemed ok. I think a strip and clean is on the books. I just seen a chap on youtube with a triumph Spitfire with a similar problem. His issue was a blown head gasket between 1 and 2 due to overboring. Just before mine conked out last week it was putting out lots of smoke, reckon it could be the same thing?

[nicklouse]

ok then. first things first do a compression test.

[Mini-Hazel-Nut]

ok then. first things first do a compression test.

Hi, I just bought a compression tester and will do the deed on sunday. I`ll get back to you with the results.

[Mini-Hazel-Nut]

Hiya, just got back from doing the comp test and here are my findings -

 

Cyl 1 - 130

Cyl 2 - 120

Cyl 3 -130

Cyl 4 - 130

 

These were done with a Clarke tester and I also checked that all valves, rockers etc were doing their stuff. What is your conclusion from this?

[mini_in_progress]

Ouch, thats low comp, id want to see 170-190 usually. That said i wouldnt expect them all to be that low together ifthere wasa headgasket issue

Edited by mini_in_progress, 13 May 2018 - 11:27 AM.

[Mini-Hazel-Nut]

Ouch, thats low comp, id want to see 170-190 usually. That said i wouldnt expect them all to be that low together ifthere wasa headgasket issue

I`m glad you said that because it more or less confirms my suspicion that the head gasket has gone. That would also explain the vast clouds of blue smoke it was putting out just before it died to say nothing of the lack of suction through the carb. Thank you. 

[Icey]

Ouch, thats low comp, id want to see 170-190 usually. That said i wouldnt expect them all to be that low together ifthere wasa headgasket issue

I`m glad you said that because it more or less confirms my suspicion that the head gasket has gone. That would also explain the vast clouds of blue smoke it was putting out just before it died to say nothing of the lack of suction through the carb. Thank you. 

Not the diagnosis I would have jumped to, sounds more like tired bottom end (i.e rings).

[Dusky]

I don't like using a compression tester to check engine health. You clearly DONT have a blown headgasket. 
All other info relies too much on variables. I can get 200 psi out of a tired engine, and I can get a very healthy high comp engine to only show 100 psi on a comp tester.
A leakdown test tells you a bit more, a wet comp test too.

back to the drawing table ;)

[nicklouse]

 

Ouch, thats low comp, id want to see 170-190 usually. That said i wouldnt expect them all to be that low together ifthere wasa headgasket issue

I`m glad you said that because it more or less confirms my suspicion that the head gasket has gone. That would also explain the vast clouds of blue smoke it was putting out just before it died to say nothing of the lack of suction through the carb. Thank you. 

 

so what other info are you not telling us?