Hi all,

Some of you may remember my engine not starting saga... 50 miles out from SVA completely standard C20XE red top engine dies pulling over from a 20 min run at about 60 mph. Couldn't restart it, no matter what we did. Compression test 70 psi all pots (though a 'dry' test), fuel, ignition and timing all apparently OK....

Hoped it was electrical, couldn't trace it, but thought might use it as an excuse to change to bike carbs - all that now on with distributor from H + H ignition solutions fitted... still no starting, even with easystart.

Losing the will to live with this one - the coolant was very low (none left in header tank) when the engine died - what damage could I have done which would stop it starting... any suggestions of what to do, or has anyone got a red top engine for sale.... if not I'll have a non running Dax for sale very very soon!

Chris

70 psi is way too low,timing belt jumped/head gasket?

Timing is fine, I'm thinking I should now take the head off it... just want to make sure that I've not missed anything else before I do that - something I've not done before and don't really want to do!

Chris

put some oil down plug holes and see if that up,s the compression,how does the engine sound as you spin it?even with 70 psi it should make an attempt on sleazy start.
is the spark big enough and are the plugs fouled/tracking down the ceramic?

70 is way to low IIRC they should be 150-175.


What was the oil presure like?

[Edited on 17/5/08 by philw]

Its not even trying, nothing at all... really really bugging me now. Just can't understand with timing, spark and fuel why it won't go.... I'd have thought even with 70 it would try.

I'll try some oil and see if it helps, but very tempted to swap the engine out.. Oil pressure is OK, and all the valves open and close (can get problems with the hydraulic followers, but that doesn't seem to be it...)

Chris

[Edited on 17/5/08 by chrsgrain]

Can't remember if you built it yourself or not, are the rings put in properly?

Not built by me, so don't know - it was running fine though...

Chris

You say 70 on all cylinders, is there any variation at all?

Have you got the throttle open when your doing the compression test?

I did 1 for the first time the other week and thought they were all a bit low...
Then I read the instructions and it says to have the throttle open.. much more like what was expected

Did the test with just the inlet manifold on! No carbs; there was only about 5 difference between all the pots - which is probably within error to be honest....

Chris

I wonder if you can do the test without the Cam cover on or if there will be oil absoloutely everywhere!

Just to check that both cams etc are opening as you turn the engine over, if either the inlet valves don't open that could have the same effect as well. It just seems strange that there all equally low figures.

Are you sure the compression tester is OK? Has it been tried on another engine for comparison?

I thought that ^^^ ! Yes, OK on another engine, unfortunately.... All the valves open and close (looking through inlet and exhaust ports) Could be that they arent seating properly, but no real reason for that...

Chris

Not impossible that the hydraulic tappets have pumped up causing valves to be off seats, have had similar problems with other engines. A cylinder leakage test would show it up if that is the fault.If you have a spark,ignition and cam timing is correct , you have fuel getting in and compression it should run As a last resort have you tried towing it to start? Have had engines that refuse to start that go with a tow and have never been a problem afterwards

How have you checked the timing?

XE's are well known to shear the woodruff key on the crank pulley.

Also, the timing marker on the crank pulley isn't worth taking any notice of, so a welding rod down #1 is the best way.

Make 100% sure your crank/cam timing is where it should be.

Sounds like the gauge. I've done the same test over the weekend for my first time, to see if shot rings were the cause of my oily-piston problem. I was getting low 120-125 psi across all pots...

Turns out, there were 2 problems:
- like MkIndy7, I had the throttle shut
- the Gunsons Hi-Gauge was reading low (seemed to be blowing by the o-ring / hosejoint)

Took it back to the shop & got a Laser Tools one from Screwfix. All 4 pots between 190-198psi...

get hold of a leak down tester. 70 psi is way to low. should see 185-200psi from a fresh engine. maybe 5% -10% less if the throttle plate is shut. You could inject the engine with air, Drill the electrode out of the sparkplug & weld/tap/braze a male pipe onto the plug casing . Connect an air line to it. safey first so, DONT inject high pressure air into the engine, MAX 80-100 psi. Set the cylinder that you are checking to TDC. Make sure all valve are in the closed position (ie cams set so valve are closed)

I hold the crank still during air injection with 24" power bar, on the crank shaft pulley, but its best to make up a tool for locking from flywheel ring gear.

if air comes out of the sump or beather the rings bores are worn. if air comes out the inlet/exhaust port, corresponding valve are bent or hydraulics have not bleed down & are over jacked . if air comes out the water jackets the block is cracked or the head gasket is gone.
A wee tip, if two adjoining cylinders are down it tends to be the head gasket that has gone.
As stated a leak down tester is what you need, but the above will give you a dam good idea of what wrong.

Andy


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