Morris Minor Owners Club

Hi all had a rebuilt engine put into a car and had it torqued on 500 miles.The car has refurbed dizzy and electronic ignition all good.Only driving at 60 mph until torque down.Went on a long drive after and all good.Afrer a while the car was lumpy in low gears and on tick over and timing when out as sounds like a kind of pinking.Can only think dizzy is playing up.Any ideas please

Hi,

When you say torque down at 500 miles do you mean the head was retorqued? I've not heard of this practice and (anyone feel free to correct me) I'm not sure it's a good idea. As far as I know, standard practice is to retorque (and then reset valve clearances) only after the first heat cycle.

Is the engine power also down? I wonder if your head gasket has blown between two cylinders, having been disturbed by the retorquing. This has happened to me in the past and it does sound like loud pinking.

Not easy troubleshooting from a distance but assuming for now it’s not the gasket, although possible, and yes 500miles sounds too long to wait to retighten, check the timing, also to eliminate the electronic ignition perhaps put the points back. Plugs and leads check for decent spark, check for loose wires etc. it may even be a fuel issue, fuel pump points.
Reading your post it sound like perhaps someone else was involved with the engine, if so maybe they have some ideas. Is this a Minor engine or some other?

In terms of timing, check that the distributor is secure and that the vacuum advance is connected. Just thinking of things that may have been disturbed.

Classiccars
Can you please confirm the make and model of the car you are referring to?
There is nothing wrong with re-torqueing the head on a 'A' Series after 500 miles so long as the head was re-torqued after completing the first heat cycle.

Hopefully classic cars can clarify but it doesn’t read as initially re torquing after first heat cycle, only after 500 miles.

Issue could be many things, I would go back to basics, check compression, check you have a spark at each plug, check the timing, check the carb dashpot has oil, a decent fuel supply, and the float level is correct check for air leaks into the inlet manifold and check the valve clearances.(I hope you did re-set these when torquing the head?).

Just to add one more simple thing to look at, check that the choke isn't stuck on. The outer sheath of the cable can ride up and jam against the hole it goes in.

If it was not retorqued after the first heat cycle then it is quite likely that the gasket has failed. If it was retorqued after the first heat cycle, then a further retorque at 500 miles will not do any harm, and I have seen recommended in several sources.

Prolonged running with a blown gasket could cause serious damage, so before running the engine further, perform a compression test. Only if compression is OK should you proceed to other tests.

Thank you all for the advice.Lots to take in but I think I will start with compression as advised and work. on from there

We’ve not heard back from you, any revelations ?

Depending on which engine and what gearing, 60mph, to run-in the engine after a rebuild (whatever that may mean) could be quite high rpm’s and a heavy load on anything resembling an upwards slope.

I am in the head gasket failure group. Even more especially, if the head and deck were not checked for flatness.

Yes 60 does seem quite high, assuming a Minor engine, running in an engine after a rebuild is quite usual.
We may yet get more answers.

When running in the most important thing is to not let the engine labour and not over rev.
60mph may be at the top end of the acceptable rev range for a 948cc but for a 1098cc not unusual.
The running in method of sticking to 30mph with a 'Running In Please Pass' stickers in the back window is old hat and is not required.
I ran in my new Honda 250cc motorcycle by taking it back to the west coast of Cumbria from a dealer in Worcestershire up the M5 and M6 in one go - 350 miles. Nice and steady did it and the engine was as sweet as a nut ever after, in fact it took me to the North Cape at the top of Norway and back shortly afterwards - a journey of over 4000 miles.
The Morris 1380cc engine was run in at the Haynes Museum track at Sparkford which I hired for the day and the engine at that time had no go under 5000rpm.

'Running in' was a recognised process you went through with a new car. Never having had a new car I'm not sure if the same recommendation applies? I believe a lot of new vehicles don't even get the oil changed until 20k!!
Personally I would certainly change oil/filter as well as considerate use.

Alan

Alan
Very few new cars get run in these days as production processes are much better/tighter.
The last new car I had a Hyundai i10 required no special running in process other than not overloading the engine or over revving the engine for long periods.
As regards oil change - my modern gets the oil and filter changed once a year (at around 10K per annum) and when its changed the old oil is still clean. A bit different to the Minor at every 3K and black oil