15 replies to this topic

[austinmayfair85]

Ladies and Gents,

 

Whilst driving along on the motorway today my 998cc developed engine knocking. I stopped to check things over and noticed the dizzy clamp was loose however the dizzy itself was still in the same position so i simply tightened it up. It then refused to start. I had air, fuel and spark so it seemed particulary odd. It took a bump start to get the engine going, and it ran pretty badly even though the ignition timing seemed ok.

 

I managed to limp home on it, however it knocks under load and has very little power or acceleration in anything above 2nd gear. Top speed is 50mph max.

 

Any thoughts as to what i am facing here?

[Steve G]

The loose clamp might be a coincidence but I would check the timing properly to start with. Becuase it's running badly it might be best to do it without starting it, you should be able to get a rough idea by setting the engine at TDC and see where the rotor arm is pointing. While setting TDC you can check the plugs to see what state they are in.

[geoff-d]

Will it start on the key now ?.

If not could be headgasket .

[austinmayfair85]

No it doesn't start on the key now

[geoff-d]

Check compression to see if it's headgasket . I have had it with a race car only starts with a bump. 

[mk1leg]

check baulkhead engine mount and see if the bracket holding it has not broken away........I have replaced several for club members laely.........also earth strap from block to baulkhead might be sospect

[jaydee]

Arrange a compression test first. Requires engine warm and 2 minutes of time.

If values are decent and you have no more than 10psi difference across the cylinders then move to the ignition side.

[geoff-d]

Have you got it sorted yet ?

[austinmayfair85]

Compression test yielded the following results;

 

1 - 25 PSI

2- 25 PSI

3 - 140 PSI

4 - 145 PSI

 

Think its fairly obvious what is going on there! Thoughts?!

[MrBounce]

I think it's a brake problem

 

Seriously though your HG sounds like its blown between 1 & 2, so off with its head it is.

[jabos7]

On the topic of compression,  I've got a smokin' (not in the good way) 998cc that just won't clear up.  I'm afraid I've let it sit too long between

start-ups, pending a restoration, and now I'm going to pay the price.

Today's compression test:

Cyl     intial       after tsp oil added

1       150        180

2       140        175

3       142        175

4       150        185

 

Do you think I'm looking at some light wear in the rings, but primary problem (smoking) might instead be up top in the valve guides/seals? 

Those initial numbers good enough to leave the short block/bottom end alone?

[miniboy1993]

I having the same problems :/

[jaydee]

On the topic of compression,  I've got a smokin' (not in the good way) 998cc that just won't clear up.  I'm afraid I've let it sit too long between

start-ups, pending a restoration, and now I'm going to pay the price.

Today's compression test:

Cyl     intial       after tsp oil added

1       150        180

2       140        175

3       142        175

4       150        185

 

Do you think I'm looking at some light wear in the rings, but primary problem (smoking) might instead be up top in the valve guides/seals? 

Those initial numbers good enough to leave the short block/bottom end alone?

 

That compression test shows piston rings wear

Leaky valve guides will show smoke at start up.

[jabos7]

How about consistent smoke that doesn't go away, even after engine at operating temps?  --Still valve guides?

[jaydee]

Nope, thats worn rings and possibly a too rich mixture