rootes engine help!!

jgra1 · Post by **jgra1** » 23 Dec 2006, 10:47

chaps, sorry this is away from French cars .. i am desperate

took camper 100 miles last night beginning of holiday, had an electronic fault.. supect the coil.. in testing that side of things out, i noticed the oil light then didn't extiguish. I removed the pressure sender and started her up.. there was no oil coming out at all..

Got recovered all the way home and guess what, the oil light is behaving fine now.. please can someone tell me what may have happened...
I want to get back on the road today, will certainly change oil and filter but what else can i do.. i dont want to flush the engine really..

John

AndersDK · Post by **AndersDK** » 23 Dec 2006, 11:11

First check will of course be the dipstick.

I've seen thick oil mud in old & neglected engines - that kind of stuff that would block oilways.
But I really doubt that would be your problem ?

If it is a chain driven oil pump setup, then a serious fault type can develop in the sprockets unlocks with either axle, i.e. a broken or missing woodruff key.
I've never heard of broken oil pump drive chains.

I would not try flush the engine. Diesel (derv), paraffin & petrol makes most rubber seals swollen. Not good for longevity of the seals.
Instead use a full synt low viscosity engine oil, like 0W30 or 5W40.
Note that these oils have a tendency to disappear out the exhaust on older and worn engines : keep an eye on the dipstick.

jgra1 · Post by **jgra1** » 23 Dec 2006, 11:22

thanks Ands..
Oil level fine... pump direct drive from worm gear on cam.. oil and general engine is clean as it had a recon crank a few hundred miles ago..

hmm

dnsey · Post by **dnsey** » 23 Dec 2006, 12:27

Sounds like an earthing fault to me, causing both the ignition and oil light problems.
OTOH, it might be coincidence - wouldn't be the first time that an oilway has become blocked after a recon.
If I were being cautious, I'd fit a pressure gauge at least temporarily to keep an eye on what's happening.
EDIT: just noticed that there was no oil at the sender port - in that case I'd certainly fit a clock!

bxbodger · Post by **bxbodger** » 23 Dec 2006, 13:14

If the motor hasn't been run much over the years it's probably a bit of sludging around the pumps pick-up, clogging the gauze : use a proper flushing oil and then fresh oil with a new filter, and a pressure gauge is a good idea!!

G4EIY · Post by **G4EIY** » 23 Dec 2006, 14:27

Hi John,

There is a possibility that you have a bit of swarf floating around, this can get stuck in the oil pressure relief valve, and hold this in the open position. The oil is then returned to the sump.

This can also happen if the oil has not been changed at regular intervals, then gunge builds up and sticks the plunger or ball in this relief valve off of the seat.

Not sure where it is located in the rootes engine, normally it is attached to the pump.

This means a sump off to check.

Good luck...

jgra1 · Post by **jgra1** » 23 Dec 2006, 15:21

thanks all will let you know..

have had sump off, the oil was metallic in places.. a little gungy.. cleaned sump, cleaned gauze, changed filter, put in 10 40.. not that thin unfortanatley...

if there is something in there,, i wonder where it is now..
roadtesting again.. M25.. AA wont recover me for same problem

J

jeremy · Post by **jeremy** » 24 Dec 2006, 09:37

Could the oil pick up seal with the sump - apparently a favorite on Jaguars but from the diagram I have I don't think this can happen as the shape of the pickup is more like the top of a bun inverted and wouldn't form a seal.

Often engines that have had new crank bearings etc will run at an oil pressure far higher than the setting of the pressure relief valve (thought my BMC diesel would wreck itself when it went to 110 and stayed there for 30,000 miles) I mention this as it doesn't support the pressure relief valve theory - as the thing would have considerable pressure and flow even with the valve open.

I don't know where the oil pressure pickup is in the circuit - but if its beyond a bearing like a shell (as will be the camshaft bearings) it is possible for the bearing to twist and cut off the oil feed holes.

Again dependant on its position - if its after the camshaft then if for example the camshaft end-float ws not properly controlled - the camshaft might cut off the flow at one end of its travel.

lolingram · Post by **lolingram** » 01 Jan 2007, 02:35

I had a pump chain let go on a P309XUD after 70k miles...

jgra1 · Post by **jgra1** » 03 Jan 2007, 21:44

ok all.. i am back

600 miles or thereabouts.. 19 mpg's although i was running around Exmoor.. so not too bad for a 1967 2 ton brick..

Anyway.. after the initial problem, changed oil and filter, no pressure light again at all . decided to risk another attempt at the holiday.

No problems..

..
..
until.. final day.. coming home.. had an ignition fault (the same as before) decided to completly rebuild distributor at side of road, refaced pitted points, changed coil, was pleased with result. Started her up, sounded fine

but.. ahh Oil Light on again, 500 miles after the first time.

Was stuck in middle of Exmoor on New years day!
Took sensor out again, no pressure, drained oil, refilled, no pressure..

stuck, called recovery and sat for 90 mins...

He came, I started the engine to prove it was finally dead..

Oil Light came on and went off!

We chatted and he agreed in part with G4EIY..
The Pressure relief valve was sticking, I summised that if I left vehicle for long enough, clearances return, valve springs back to normal, and all is well! nightmare..

drove the van 250 miles the next day, have got home all is fine

rest assured I will be buying a new complete oil pump this week.. what a trip...!

John

PS What causes 'running-on' ? Retarded igntion?

AndersDK · Post by **AndersDK** » 03 Jan 2007, 22:50

jgra1 wrote:PS What causes 'running-on' ? Retarded igntion?

"Running-on", "after burning" or "glow ignition" is caused by 2 things :
1) fuel admitted to engine after ignition removed
2) spark plug electrode or carbon deposits glowing red hot to ignite admitted fuel (i.e. not ignited by sparking)

I believe that a 1967 carburettor may not be fitted with the "feature" of an air electro-valve. If its got one - then its obviously not working. Its purpose is to lean the idle fuel admission such the mixture wont ignite.

Glow ignition can be caused by a too hot spark plug type - or by the engine running too hot - in turn caused by retarded ignition. This would also lead to a high consumption.
Ignition can be retarded both static (by setting) and dynamically by vacuum advance or centrifugal advance not working while engine is running.
Always check the ignition timing dynamically with a strobo light with a hot engine. The strobo light will immediately show any missing dynamic timing advance.

jeremy · Post by **jeremy** » 03 Jan 2007, 22:58

Running on is caused by something providing a source of ignition other than the intended spark - so you are looking for something that's too hot.

From what I remember the Rootes 1725 - in both iron and alloy headed form had simple bathtub combustion chambers without any sharp lump or corner (not like BMC with the projection) - so there's no particular feature to cause the problem.

So something must be too hot - sparking plugs must be the correct grade (or harder - ie cooler running - smaller number if Champion - not sure about others)

Air leaks may cause it to run slightly hot but would I'd have thought have given a bad idle - as may a weak mixture or an over-advanced ignition.

I presume you are running it on unleaded fuel - which is 96 Octane. To be fair to it I ran our late and unlamented Mini on it after converting to unleaded (valve inserts etc) without adjusting anything and didn't need to. However if you have the alloy head the original compression was 9.2:1 (Holbay 9.6:1) and if the head has been planed its probably a bit higher by now. Originally this would have required something like 98 octane - so it could be a compression issue.

Finally - is the idle at all fast? - are the carbs in sync or is one a touch weak - Both of these could cause the problem.

lolingram · Post by **lolingram** » 03 Jan 2007, 23:09

From what I remember the Rootes 1725 - in both iron and alloy headed form had simple bathtub combustion chambers without any sharp lump or corner (not like BMC with the projection) - so there's no particular feature to cause the problem.
_________________

Also worth perhaps remembering is that this engine was never designed to run on low octane lead free petrol...

Certainly fed a diet of 98+ Octane leaded (not 92 Octane no lead) it would not preignite IMHO.[/quote]

jeremy · Post by **jeremy** » 03 Jan 2007, 23:27

British unleaded is 96 octane and from my limited experience of the stuff isn't prone to pre-ignition - and I'd say it performs better than its leaded equivalent.

jgra1 · Post by **jgra1** » 03 Jan 2007, 23:29

thanks all..

I have been running on ?95 ? unleaded.. I did hear from a humber engineer who built this type of engine that the vavle seats could take lead free, but by the sound of it, the octance rating is more an issue then the lead content. Will begn to use additive/high octane Also will do a static timing set and recheck with strobe...

Engine (now) has Alloy head engine 9:2 - 1

Idleing has become high after engine is warm.. uncomfortably high...

J