Engine trouble

[hvannieuwkoop]

Hello Friends

I have been having some challenges with my 1950 918sv Morris Minor. Here is what I observed:
-top speed of 60km/hr
-sounds like one valve is ticking a little bit as it runs. (valve adjustment may fix this I guess)
-the engine stutters a bit at higher speeds.
-wet/dry compression test on a warm engine both at around 100psi.
My assumption is that this is most likely a valve problem. Could it be anything else? I if I end up putting in new valves what other work should I do while I have the engine apart? New valve seats? is that expensive? I plan to repaint the whole vehicle and will likely take the engine out so that will be a good opportunity to do the engine work.

Thanks,
Henk

[RobThomas]

100 psi? Well, normal atmospheric pressure is about 14.7psi so 100 psi is about 6.5 times that. 6.5:1 compression sounds about right for an MM. Can you hear any uneven hissing through the exhaust pipe when someone else turns the cranking handle?

The best I've ever got from my MM with a good engine was 56mph (90kph) indicated so worth looking at carb, timing and speedometer accuracy. GPS is more accurate.

[colin addison]

Henk
Maybe you should look at the timing. I have found that the best way to do it is to find a decent hill (maybe not so easy if you are in NL??) advance the dizzy just a little and then try it. Also the acceleration and top speed will improve significantly on the flat if it has been too retarded, and you will be able to reduce the choke demand as you advance it. When and if the engine starts pinking then retard a bit.
Mine will now get up to the mid '50s (mph) relatively quickly on the flat.
Colin

[amgrave]

If it was a valve problem I doubt you would have even pressure readings on all four pots.

[hvannieuwkoop]

Thanks a lot!
Next time I'm working on it I'll need to do what you suggest. I'll try get to it this afternoon.
-I have been using my GPS for speed since my speedometer waves up and down. The faster I drive the faster and more dramatically the needle waves from one side all the way to the other. Any suggestions on that?
-What wuold uneven hissing out of the exhaust mean when handcranked?
-has anyone had the dizzy stuck even after loosening the clamping bolts? How would I loosen it without breaking things?

I'm in BC Canada despite my Dutch name so finding hills or mountains will not be a problem
Henk

[RobThomas]

HISS, HISS, huff, HISS would show a leaking exhaust valve, as would a different feel when turning the cranking handle 2 revolutions to go though all 4 compressions.

If you have a later head with a thermostat on the head then the pich bolt might need to be knocked back a bit. It is a bolt with a semicircle cut out of it that allows the distributor to be slid past it but then clasps it when the nut is tightened. I expect someone on this website has a photo of it somewhere.

[hvannieuwkoop]

I doubt I have a thermostat as I don't have a water pump either. Would tapping the base lightly with a hammer work to loosen it or using a wrench to turn the dizzy work? Don't want to damage things!

[hvannieuwkoop]

Hello

I loosened both the nut and the bolt holding the dizzy from turning. To adjust the timing if I understand correctly I only need to loosen the nut and bolt clamping the dizzy, but I wanted to be sure I had the unit loose so I lossened the other bolt that goes into the head as well. I tried tapping the base of the dizzy with a hammer, and turning it with a wrench, but I got no movement (rotational or vertical). I sprayed some WD40 in between where the dizzy goes into head and put quite a bit of pressure on it, but didn't want to overdo it as I'm worried I'll break something. Am I doing something wrong or what is going on??? Please help!

Thanks,
Henk

[Redmoggy]

Keep soaking it in WD40 and occasionally trying to jiggle it. If every thing is loose it should move. Whilst your at it I would suggest checking the mechanical advance is free and the springs are not loose on their pins.

Rod

[RobThomas]

I would expect that there is some corrosion between the cast iron head and the alloy bodied distributor that has effectively glued the two parts together. There is nothing else to hold it in so persistence and heat/WD40/Release Agent etc will get there eventually.

[TvdWerf]

I have 2 engines partial mounted in my garage, and one rebuild in the car.
The one in the car is rebuild by me.
I have also a spare head, together with an old ignition, this makes it easy to look.
So when you are not far from Assen/Groningen/Drachten, you are welcome to take a look ;)
Without a water pump, the thermostat house should be empty, just like mine.
Taking the old engine apart, needed a lot of WD40, and waiting, sometimes with help from a little heat from my propane burner.

[hvannieuwkoop]

I have 2 engines partial mounted in my garage, and one rebuild in the car.
The one in the car is rebuild by me.
I have also a spare head, together with an old ignition, this makes it easy to look.
So when you are not far from Assen/Groningen/Drachten, you are welcome to take a look ;)
Without a water pump, the thermostat house should be empty, just like mine.
Taking the old engine apart, needed a lot of WD40, and waiting, sometimes with help from a little heat from my propane burner.

I live in Canada, but want to visit Holland one of these years! I may take you up on the offer then:)

[hvannieuwkoop]

Thanks for your help! I went through a whole bunch of WD40 and managed to turn it little bits at a time. I did scar up the aluminum base of the dizzy but thats the way it is. I need to spend more time adjusting but I did manage to change my top speed from 60km/h to 70km/h! Things are looking up. Now it does sometimes just stalls when I let the gas go. Could that be the carb damper causing that to happen?
I also found out today that classic car owners wave at each other (I'm a newish classic car owner)! Such friendly people:)

[TvdWerf]

You have a Dutch name ;)
I have to work in Canada this summer, but my experience is that Canada is too big to visit all

[RobThomas]

When I was 19 I delivered aircraft from the UK to Can/US. Coming from here it was particularly hard to get to grips with the distances involved in travelling. Also the population density is 40 times less than Wales. Not as easy to find things that you need in a hurry. Thank goodness for Ebay!

Henk. Do you have a copy of the Morris Workshop manual?

http://sucarb.co.uk/carbspec/carburetto ... s/id/1896/
The screws in items 17 and 18 adjust the idle and the fast-idle-on-choke.

[TvdWerf]

My job is in the agriculture automation, on my list are machines to deliver in the UK, Africa and Canada this summer. And also a short holiday in September nearby the auto jumble ;)
I have also some extra manuals and spare part lists on paper, original.

[hvannieuwkoop]

When I was 19 I delivered aircraft from the UK to Can/US. Coming from here it was particularly hard to get to grips with the distances involved in travelling. Also the population density is 40 times less than Wales. Not as easy to find things that you need in a hurry. Thank goodness for Ebay!

Henk. Do you have a copy of the Morris Workshop manual?

http://sucarb.co.uk/carbspec/carburetto ... s/id/1896/
The screws in items 17 and 18 adjust the idle and the fast-idle-on-choke.

Yes I downloaded a copy! Super helpful

[hvannieuwkoop]

Ok I got up to 74km/hr today. I also found out that there is too much play in the throttle cable. This means when I press the gas pedal to the metal the throttle is not completely open. I adjusted it a little and right away got more power! Something that simple! Can't believe I missed it!

Now it has a hard time starting, but I had been playing with ignition timing so that may need some more adjustment.
Slowly but surely I'm making progress!!

[colin addison]

Henk
Better already, keep at it!!
Colin

[RobThomas]

Just a thought, is the distributor mechanism free internally to rotate? The usual "grab the rotor arm and see if you can twist it slightly" idea. Could the advance mechanism be as seized as the clamping bolts were?