Bringing a 1939 '10 engine back to life

[stuartbell]

Further progress;
Firstly, an excellent New Year's Eve present turned-up from Mike Couldrey, which has meant that progress could be made at-all. A nice shiny new cyl. head gasket has meant that the cylinder head could be returned to its rightful place, and a set of new head-bolts should ensure that it stays-put. The tightening-down of the head, performed in three stages throughout (10lb/ft, 20lb/ft, 30lb/ft) went very well, with no signs of distortion of the gasket betwixt the middle two cylinders, which is a relief. All the critical areas of the head faces were treated with Red Hermatite, which will make the removal a bit more "interesting", but will ensure that the passages remain tight during initial running.
Secondly, the oil system appears to be functional and reasonably tight at all the critical points, except (perhaps) the rocker assemblies; all rocker locations along the shaft are worn to varying degress, but no question at-all that a new shaft is required before any serious running of this engine. Despite this, a cold pressure of 50psi was easily achieved during the external priming, and maintained at this level for many seconds. A light turning of the engine did not result in a pouring-forth of new oil from underneath the engine!

So the next steps tomorrow will be to repair and test the coolant circuits, then hopefully a run during the early part of next week.

[stuartbell]

Is the clutch free?

Tim, that is the question, indeed...

Since last week, we have been pondering as to how sticky the clutch should be; the initial examination of the clutch control would suggest that the mechanism is oiled, but seems sluggish to return after pressing the pedal. What we know for sure is that the flywheel is on 180degrees out, as the old girl is timing happily on cylinder 2, rather than 1.

What I am hoping to do is to get her running and warmed-up, then let her cool down and see if the clutch is free at that point. If she will engage a gear with motion on the engine, I'll be surprised....

[jefflee]

Hi Stuart.
To bring all timing marks back into line.
Take off distributor cap, remove points & mounting plate, remove centre screw from cam,
lift cam from bob weights turn 180' and replace, this will put rotor arm round 180'.
then move HT leads to suit.
This should take all of 15-20 minutes and be easier for timing in future.
cheers Jeff. Lee.

[stuartbell]

Hi Jeff, thanks for the suggestion... although I have just put the distributor back in to engagement tonight...but it doesn't worry me too much that the flywheel is 180degress out, just something I need to fix when I get to the clutch

Good progress overall today;
a) Distributor rebuilt and fitted
b) Cooling circuits now all complete (new hoses and repaired steel pipework)
c) Coil tests OK, good spark and good condensor (I left the original inside the distributor, as the new nominal replacement seemed to have a low capacitance)
d) Starter motor smokes like a chimney from the commutator and brush box, but only because it is oil contaminated and needs new brushes. Nonetheless, the starter is cranking fine, and it looks like the commutator will clean and re-cut with minimal effort in the near future
e) Engine dynamic cylinder pressures are all complete. Peak cylinder pressures are even across all four cylinders, but the timing characteristics of the inlet/exhaust valves are bizarre - I will post the results ASAP, but I have a theory about the camshaft profiles on these engines that stacks-up with the canyon-sized warm tappet clearances of 10"thou. So far, the tappets are only set cold (10"thou), so the measured results may improve with hot-running & setting. I hope to post some data on this engine, and get some data online for other diagnostic Engineers to use!
f) Breather hose replaced with new
g) Tappet cover re-shaped by planishing around the fixing stud holes (previously overtightened) and a welded repair made to the breather banjo fixing affair within the cover
g) oil pump confirmed good on cold oil
h) oil gauge pipework porous !!

Tommorrow should hopefully bring a) pictures, b) first running video !!

[stuartbell]

Well, today should have brought a running report, but progress was a little slow this morning. Having got the sparking plugs into the engine, it was clear that compressions measured yesterday on the oscilloscope were a) real , and b) poor. That is, the compression feel on the starting handle was next to nothing, which backs-up the data from yesterday which suggested that the compression ratio was around 3:1 !!

Having got to the point where we could start the engine this evening, lack of compression has halted progress. Various theories abound, but the fixes tommorow are going to be;
a) Reset the cold tappet clearances to much wider settings - perhaps go to 20"thou clearance for starting - as this will improve the appaling valve timings seen yesterday on the oscilloscope, and hopefully allow the engine to pump more efficiently
b) Refill the cooling circuit with hot water and allow the block temperature to soak upwards
c) Maybe put a little more oil, just a few cc's, down each bore to help the piston rings seal better. There was definitely a trend on each cylindr pressure trace yesterday that continued compression was depleting the peak pressure at each stroke during the engine cranking, so as each cylinder was tested, the peak pressures decayed to circa 4.5bar absolute. This is not enough to start the engine (as proved by tonight's fruitless cranking-over!)

What I know for sure is that the valves are sealing on their seats, but maybe they are not timed correctly due to tight cold clearances on the camshaft lobes. Does anyone have a good "cold" figure for the 10hp tappets clearances around 1939?

[luli]

I post here the relevant service buletin, as had been sent to me many years ago by the sevice department of the Rover company. Having recently overhauld a Rover 10 engine, I can tell that the compression is 110, valve clearance should be exactly .010" . You can see pictures and more here:
http://lulisml.wordpress.com/2014/05/13 ... %99%D7%93/
and here:
https://lulisml.wordpress.com/2014/08/2 ... %9B%D7%93/ (and in between)

THE ROVER COMPANY LIMITED A. 466
Sheet 1 of 4 sheets.
SERVICE BULLETIN.
SUBJECT : valve and ignition timing.

MODELS : All models 1934-47

Engines used on the above models fall into two groups for tappet clearance, two groups for valve timing and three groups for ignition timing as follows :-
Tappet Clearance.

Group 1. 10, 12 & 14 h.p. 1934-37 Group 11. 10 & 12 h.p. 1937-47
16 & 20 h.p. 1937. 14 & 20 h.p. 1938-47

Valve Timing.

Group 1. 10 & 12 h.p. 1934-47 Group 11. 14 hp 1934-38
14 h.p. 1939-47
16 h.p. 1937-47
20 h.p, 1937-40
Ignition Timing.
Group 1. 10 & 12 h.p. 1934-36 Group 11. 14 h.p. 1934-38
Group 111. 10, 12 and 14 h.p. 1939-47
16 h.p. 1937-47
20 h.p. 1937-40
Before timing is commenced, reference should first be made to Part 1 Flywheel Marking, after which the group concerned for the subsequent operation should be ascertained and attention transferred to the correspondence section of the text.

PART 1 FLYWHEEL MARKING (ALL MODELS).

The markings on the flywheel .are as follows:-

The mark T.D.C. indicates when No. l and No.4 (4 Cylinder engines) or No (6 Cylinder engines) pistons are at the top of their stroke.

The mark E.P. when brought opposite the pointer on the clutch housing indicates that the No.l. EXHAUST VALVE should be at the peak of its lift (fully open).

The letters F.A.4 (4 Cylinder engines) or F.A.6 (6 Cylinder engines) indicate the FIRING POINT. When the mark accompanying these letters is brought opposite the pointer on the clutch housing, the distributor points should just commence to seperate.

As flywheels for 4 cylinder and 6 cylinder models are dimensionally identical, some may be found bearing both F.A.4 and F.A.6 marks; Care should be taken to use the correct mark when timing.

NOTE: In some instances the letter S.F. Adv. have been used instead of F.A.

Firining Order.
All 4 Cylinder models 1,2,4,3.
All 6 Cylinder models 1,5,3,6,2,4,

PART 11 TAPPET CLERANCE.

The correct tappet clearance on both inlet and exhaust with the engine HOT are :-

GROUP 1, Tappet clearance .005”.
GROUP 11, Tappet clearance .010”.

NOTE : The later type camshaft as used in GROUP 11 may have been fitted to models in GROUP 1, thus necessitating .010" tappet clearance on engines irrespective of their yoar of manufacture. It is essential, therefore, when cabling with GROUP 1 models, that reference be made to the instruction plate on the rocker cover for details of the correct clearance.
It cannot be emphasized too strongly that the clearance must be correct and the engine must be hot. If anything less than the indicated clearance is used, a fall in power output will follow and any greater clearance will mean noisy tappets.

PART 111 VALVE TIMING.

A. TIMING CHAIN OIL SPRINKLER.

All models 1934-46

It is important that the timing wheels and chain obtain adequate lubrication from the oil sprinkler, This point should be checked at all times when the front cover is removed, particularly when new wheels or chain are to be fitted. Whenever there is any evidence that the oil flow is insufficient a new sprinkler unit should always be fitted, or the life of the new parts is likely to be considerably shortened.

B. RE-TIMING THE ENGINE.

If the chain should have been removed the procedure to re-time the engine is as follows:-

GROUP 1. The mark E.P. is 108 before T.D.C. (29 Flywheel teeth).

1. Set tappets as instructed in Part 11.
2. Rotate camshaft in running direction until No.l. EXHAUST VALVE is fully open.
The use of a dial indicator is the only reliable method of determining this point. It should be mounted on an adjacent rocker shaft stud by means of a small right-angle bracket and with its aid the possibility of an error in determining the exhaust peak is eliminated. It is possible to do the job correctly without a dial indicator, but much time is wasted and the possibilities of an error very much magnified.
3 . Rotate engine until E.P. mark on flywheel is in line with the pointer in the clutch housing aperture.
4. Fit timing chain.

The camshaft chain wheel is fitted with several keyways, that if the timing will not come correct in the first position, alternatives are provided.

GROUP 111. The mark E.P. is 108° before T,D.C. (29 flywheel teeth).

1. Set tappets as instruetructed in Part 11.
2. Assemble timing chain and chain wheels in any position, using one set pin only.
3. Adjust timing chain by slackening the dynamo bolts and pulling the dynamo away from the engine.
4. Rotate engine in running direction until No.l. EXHAUST VALVE is fully open.
The use of a dial indicator is the only reliable method of determining this point. It should be mounted on an adjacent rocker shaft stud by means of a small right-angle bracket and with its aid all possibility of an error in determining the exhaust peak is eliminated. It is possible to do the job correctly without a dial indicator, but much time is wasted and the possibilities of an error very much magnified.

5. Remove set pin from camshaft wheel.
6. Rotate engine until the E.P. mark on flywheel is in lino with the pointer in the clutch housing aperture.
7. Three of the holes in the camshaft wheel should now correspond with in the camshaft iteslf. If they do not, lift off the wheel and rotate one tooth in either direction, taking care that nothing else moves also. In one or other of those positions the bolts will register.
8. Fit bolts, check timing again and if accurate, fit new locking wire through the holes provided.

PART IV IGNITIOIN TIMING.

If the distributor has boon removed for any reason, it becomes necessary to retime as follows:-

GROUP 1. The F.A.4 mark 11° before T.D.C. ( 3 flywheel teeth).
1. Rotate the engine until the F.A.4 mark on the flywheel is in line with the pointer in the clutch housing aperture with both valves on No.l. Cylinder closed.
2. The rotor arm of the distributer should now correspond with No.l Cylinder H.T. lead terminal. Should the engine have been stripped and re-assembled the rotor may be up to 180 away from the No.l. Cylinder position; in such cases remove the oil pump and rotate the pump and distributor driving shaft in the required direction until the correct position is obtained. The oil pump is inside the sump, which should not, therefore, be fitted until the timing is definitely correct.
3. Set the ignition lever en the steering column in the FULLY ADVANCED position.
4. Set the distributor points just opening; to do this, slacken the pinch-bolt on the ignition lever under the distributor head and rotate the head bodily the required amount and re-tighten the pinch-bolt. The correct gap for the points when fully opened, is .012".

GROUP 11. The F.A.6 nark is 16° before T.D.C. (4-1/2 flywheel teeth).

The procedure is the same as for Group 1. except that the sump need not be removed in order to rotate the oil-pump through 180.

GROUP 111.The F.A. mark is:-
10,12 h.p. 1939-47 11° (3 flywheel teeth)
14 h.p. 1939 8° ( 2 flywheel teeth)
14 h.p. 1940-47 11° ( 3 flywheel teeth)
16 h.p. 1937-39 8° ( 2 flywheel teeth)
16 h.p. 1940-47 11° ( 3 flywheel teeth)
20 h.p. 1937-39 12° ( 3i flywheel teeth)
20 h.p. 1940 11° (3 flywheel teeth) P.T.O.
before the T.D.C. mark on the flywheel.
1. Rotate the engine until the F.A. mark on the flywheel is in line with the pointer in the clutch housing aperture with both valves on No. l cylinder closed.
2. The rotor arm of the distributor should now correspond with No. l cylinder H.T. lead terminal. Should the engine have been stripped and re-assembled the rotor may be up to 180 away from the No. l cylinder position; in such cases remove the oil pump and rotate the pump and distributor driving shaft in the required direction until the correct position is obtained. The oil pump is inside the sump, which should, not, therefore be fitted until the timing is definitely correct.
3. Set the octan selrctor at '0' on the sliding scale.
4. Set the distributor points just breaking by slackening the 1/4” pinch-bolt at the base of the distributor head and rotate the distributor bodily in the required direction. Do not forget to re-tighten the pinch-bolt. The correct gap for the points when fully opened is .012".

Octane Selector.

The octane selector is fitted direct to the disttibutor head and comprises a sliding portion controlled by an adjusting screw. A calibrated scale marked with R (retard) and A (advance) with a number of divisions between is provided.
The ignition is normally set with the line on the sliding portion against the '0' on the scale, thus leaving two divisions further possible advance and five divisions further possible retard. This position is correct when using a high octane value petrol and with a clean engine, but should it be necessary at any time to use a low grade petrol or should pinking develop as a result of a need for decarbonising, the control can be retarded a little by turning the screw in an anti-clockwise direction. Do not forget to revert to the original position when again using high grade fuel or after decarbonising, as only in that position will the maximum performance be obtained.

[stuartbell]

Having started-out today with the knowledge that this was "last chance saloon" with regard to the work on Lucy, the very first job was to sort-out the starter motor, as it was clearly incapable of starting the engine! Extracating the motor from the side of the engine required removing the starter housing on this car; the motor is marked "Special Equipment" and may be larger than normal? Certainly, what we found this morning was that the motor is too large to clear the oil pump retainer bolt-head, so we had to fully remove all the fixings to the flywheel housing to generate enough clearance. On strip-down of the motor itself, waht we found was that the commutator and brushes/box were badly contaminated with, what we believed to be, grease from the shaft end-housing. The amount of arc-ing over of the brushes had generated enough heat and errosion to create further problems between the brush boxes and alloy support plate, so the whole lot had to be cleaned and degreased, before new insulator washers and fixings were made-up to reattach everything.

In parallel to the starter motor work, the rocker cover was removed (once again) to allow a dial test indicator gauge to be mounted over the exhaust valve for cylinder_2 (Lucy has the flywheel on at 180degrees error) so that my theory about the camshaft timing could be confirmed. Without any doubt, the camshaft is presently one flywheel tooth retarded from its correct position (confirmed on cylinder_3), which is corresponds exactly with the wear seen on the timing system; the engine times correctly if it is turned backwards, suggesting that the wear has occurred on the drive-side of the chain/gears only, and that the engine remains "as-built" from the factory for the camshaft gear positioning to the camshaft. As the data I took yesterday suggested that the retarded exhaust valve closure was creating a problem for the induction system, I opened the exhaust valve clearances to 15"thou cold, for the purposes of getting this engine started.

In addition, the bores were all treated to several shots of SAE50 (heavy) oil direct to the tops of the pistons, to try to raise the compressions.

After a slow start this evening, she eventually spluttered into life, again requiring a couple more shots of oil to the two rearmost cyclinders, which were reluctant to get compression. So Lucy lives again!

[stuartbell]

The final day for working on Lucy, sadly.....

The best news is that the compressions that we managed to restore yesterday during the running-in have maintained themselves; turning the engine over on the handle this morning, all four compressions were good and balanced across the cylinders. I removed all of the sparking-plugs, once again, to make a series of dynamic in-cylinder pressure traces for the four cylinders under engine cranking. All four looked to be good, in-fact the troublesome cylinders 3 and 4 from yesterday were now the best! All four achieved a minimum peak pressure of 7BAR gauge pressure, which is very good.

The coolant was drained-down to reveal very little rubbish had been disturbed from yesterday's running, so we are happy that the debris was properly cleared from all of the passageways.

The starter motor showed no signs of repeated arc'ing over at the brushes, so that repair has been deemed a success. I am not intending to make further repairs to this unit, except to skim the commutator at some convenient moment; the run-out on the contacts is a little poor, but the motor works efficiently enough for me.

The head bolts were all to torque away from the fire-rings, but those nearest the fire-rings snugged-down by 1/2 to 1/3 a flat on the fixings to achieve a 30ft/lb torque figure again.

Finally, Lucy was pushed off the ramps and tucked-away for the time-being. I now know that I have a good engine, albeit one with a work-list to tick-off; timing-gear needs attention, flywheel needs correcting (the clutch is actually siezed, as Tim suggested), the oil pump drive needs improving for backlash, the oil gauge hose needs replacing, the water pump leaks from the shaft (like a sieve!) and needs a thorough rebuild, and the carburettor needs a basic tune to lean-off the mixture a little.

I will attempt to link the photos and the starting-up video correctly over the next few days, time permitting...

[TimMoore]

Shame work has to stop. Hopefully you won't need the incentive of a pal arriving to recommence.

Clutch might be a problem involving gear box out...freeing a seized clutch by severe means without opening things up is a bold adventure necessitating as you know some non - gentle machinations....hurtful to an engineer like you and tough on an old lady approaching 76 years of age....

Water Pump is no surprise sadly. Mike Evans is your man there, send him your pump, he rebuilds them.

In 1955 my Dad sold his Blue 1939 Rover 10 he'd owned since new for £5.00 purchase from Colliers in Birmingham by his parents as a 21st birthday present for him, lucky man at the time.....

He stored it on blocks during WWII and could have sold it in 1946 for a fortune when cars were so scarce but elected to keep it....

It was towed away, I can still see it leaving behind a Rover 12 now......

Reason sale was couldn't get then easily a new water pump! Still £5.00 for a non running car then 16 years old probably wasn't bad, my first car a 1947 Austin 10 was purchased with 3 weeks MOT and a few weeks road tax in 1966 for the princely sum of £2.00......really!

[stuartbell]

Tim,
Yes, I did try to free-off the clutch whilst the engine was running - but forgot to "give it some beans" after the engine had cooled once again. If I can get the link for the video (a dialed-down low resolution version) of the eventually successful start-up, then you can just hear my ham-fisted attempt to select 4th gear after a few minutes! I haven't had any lessons, but I can play a good tune......

To be honest, I never thought that the clutch would be free after all this time, and having committed myself to removing the engine to make a decent job of the timing components, then it is not going to be too much more effort to heave the whole powertrain out of Lucy (which I can even do within her resting-place) and make an inspection of the flywheel and clutch with the gearbox split away on the floor. This is something I can do at my leisure, in-between the "paid work" that affords the luxury of such cars.....

Even if i cannot get all the photos and videos linked, I'll try to get over soon to Portree with the laptop for a blether. Power cuts permitting!