Lynx II, hull # 4225

[super dave]

Well Gents I need some input to a problem I came into well setting up Peters engine on my test stand as I am going to run the motor up for a while to make sure there are no problems with it before I ship it out. The problem came when I was going to install belts on the pulleys and noticed that the lower Crank pulley was off quite a bit compared with the water pump pulleys. I removed the lower crank hub pulley to see if I could spot the problem and it wasn't until I compared it with another 2 grove and single grooved pulley that I measured it against that there was 3/8" difference between the other 2 pulleys. Now here is the thing, Peter sent me his water pumps and the lower Crank hub pulley from his engine and he said that it all lined up ?? I installed a single grooved generator and one off a carrier and both lined up with the water pumps. The lower crank hub pulley that is for the Lynx is sort of special as the fan bolts to it not like most of the other setups.

Does anyone have a close picture of a stock Lynx lower crank hub pulley That I could see as I am at wits end trying to figure why its longer than the stock units making it stick out the 3/8" further. I measured the back side of the pulley to the lower timing cover bolt (see pictures) and it comes around .550 but the carrier/CMP double grooved pulley is at .380 which lines up perfect. Also the pulley is fully seated against the lower cam gear.


Help Help Help

[chris vickery]

Longer crank?
Maybe have to have the pulley shaft shortened.

[Lynn Eades]

Does the pulley have a part number?
I'd at least go to the parts book and find out if this is the correct pulley.
The Lynx was probably not the only crank driven fan.
Maybe one of the other Lynx owners has the answer?

[super dave]

The pulleys part number of C 29SR-6312 matches the parts book which Peter sent me. I asked him to send me the measurement of his generator on how far the pulley stands out which seems to line up with the water pumps.

Chris, I already thought of shorting the pulley but the seal surface would not be correct ant then the crank shaft would be sticking out past the pulley so that would not work.

The weird thing is that they all lined up on the engine that came out of Peters lynx and he sent me the water pumps and the lower crank hub pulley from it and I got him to measure the crank snout from the cam gear and it measures the same as the engine I built him

Here is a picture that Pete sent me of his engine.

[David Dunlop]

Is there anything different going on with the front face of the two blocks?

David

[chris vickery]

Maybe David is on to something. Was a different block used or the original one?
Maybe you will need to make spacer shims for the water pumps

[David Dunlop]

Looking back at earlier photos of Dave's engine rebuild, there seems to be a small casting that bolts to the face of the block, bottom dead centre at the front. The pulley assembly then fits over the shaft protruding through this small casting.

Is that casting original to the Lynx engine? If it is, everything should fit. If it is not the original casting, perhaps it is longer and causing the problem. The engine Dave is working on has a constant plane across the face of it, no recesses or protrusions for the water pumps, so if all the right pieces are attached to it, they should all line up. So now I am thinking a rogue part might be the problem.

David

[Lynn Eades]

Dave, there appears to be two key ways in the Lynx pulley? One is notched deeper than the other? Did you have it fitted with the deep notch to the timing gear key? The only thing there is the timing gear which probably lined up fine with the cam gear, otherwise you'd have noticed. So, does the Lynx gear have a rebate in it to allow the longer notched end of the pulley to go further in?
Unless there is a difference in the crank, which I doubt, then it has to be right there. You dont have any spacers other than the slinger?(which fits over the key)
You might have to remove the timing cover to compare old and new?
Good luck!

[super dave]

The crank hub pulley can only go on so far as it bottoms out against the lower cam gear. the crank shaft end is around .120 recessed at the end so that the washer and bolt can hold the hub pulley on tight ( See picture ). The key way and the notch are on all of the ford lower pulleys as the notch at the end is to fit around the timing gear key way and the long slot is for the key way on the hub itself. I had peter measure the end of his crankshaft (see picture) from the cam gear to the outer snub and its the same length as the engine I have built for him.

One more thing is that I asked peter to measure the Generator mounting flange (where it bolts to the intake manifold) to the center of the first grove of his pulley and it pretty much lines up with the water pump I have on this engine.

[Peter Duggan]

Guys,

Mother Nature has decided to intervene and tinker with the schedule for the Lynx restoration. I had to undergo some radical non elective surgery in a neighbouring province. Results are very positive and prognosis is great. However it does mean that there won't be much garage time for me this winter.
On the good news front, Dave Good has got my replacement 239 engine up and running. Another major milestone met!!!

Peter

[Peter Duggan]

Guys,

Trying a new technique for loading pictures. These are of the new rear fenders. Also having the outside storage bins being fabricated. Chomping at the bit to get back into the garage.

Peter

[Peter Duggan]

Guys,

I'm now able to put time in the garage. Great to be back working on the Lynx. Now working on the soft skin components, some interesting angles on some of these parts, due to the configuration of the hull.

Peter

[lynx42]

Hi Peter, Back home from hospital yesterday (only 8 weeks this time) and still need another back operation in the new year.

It is interesting to see the differences between the Mk.III* of April 1943 and your rear bins.





Here are two photos of my bins taken from above and you will see that the lid is bigger and hinged closer to the hull and are of a different opening shape.

Regards Rick.

[Peter Duggan]

Rick,

Glad to hear that you're back home, just wish it wasn't a short term visit.

The changes between marks is adding up. I noted the differences with the storage bins and rear fenders between Reg Hodgson's Lynx (Mk 111) and the Lynx 11 at the CWM. Fortunately enough of my originals survived to confirm that they were the same as the Lynx 11 at the museum.

Not sure if this will help you, but I stumbled across the right map case with the back supports for my mark of Lynx. Great feeling when you come across NOS parts that just slip into place.

Great to see more pictures of your Lynx, they are great motivators.

Best of luck in the New Year with your surgery. Peter

[Mike Cecil]

Reg's Lynx was in the same Australian 'batch' as Rick's.

Reg purchased it from South Australia.

Mike

[Peter Duggan]

Guys,

Christmas came in a plain crate. Thanks to the great workmanship of Dave Good aka Super Dave, I now have a reconditioned 239 for the Lynx. Dave even ran up the engine as part of the rebuild.

Now to finish a few items in the engine compartment and the engine itself and I will move on to a major milestone.

Peter

[charlie fitton]

OK - all well and good - but I've been losing sleep over the pulley problem..

[lynx42]

Hi Peter,

Your engine looks pretty good to me, but do you have the correct intake manifold? According to the Canadian Lynx I Mk.III and III* (SC F1 and F2) from hull number 1069 the carburetor was reversed so the the fuel bowl faced the front of the vehicle not the rear. From your photos it looks to me that the carby is facing the front of the motor not the rear as it should be. (Of course they may have changed it around further down the production run, but I don't think so.)

Here is a copy of the relevent bit from the manual on page Q-8.



Regards Rick

[Peter Duggan]

Charlie,

Welcome to the club. I have decided to defer installing the engine until I can sort out the issue with the pulleys. I did temporarily install the generator to see how those pulleys lined up with the others. Seems to line up better with the crank pulleys. Both seem to stick out further than the water pump pulleys.

My original engine was stamped C81T-LH on the LH head while the rebuilt engine has C7RA-A cast on the LH head. I have yet to find any differences between the two engines. The shaft from the crank is 3 1/16" from the edge of the block to the end on both engines.

I brought the Lynx home to keep me challenged both mentally and physically. She's doing a great job. Tomorrow is another day.

Rick,

Sharp eyes. I didn't pick that up until I went to install the generator. Wish all fixes were that easy.

Guys,

I welcome all and any suggestions.

Peter

[super dave]

From looking at your pictures I would say you need different water pump pulleys as shown in this picture which stick out further as you can see the pulley groove is almost flush with the end of the shaft compared with the offset ones you have now.

[Wayne Hingley]

I think you are right Dave. Can the current pulleys be flipped around, so the offset is toward the end of the shaft?

[Lynn Eades]

The C81T heads are "handed" left (6049) and right (6050) These are for pre 42 engines.
while the later C7RA heads fit on either side. The early heads fit the early blocks, but need to be relieved at the valve chamber to fit on the later blocks.(the valve line was moved up hill in the 42 engines)
The C7RA heads come in either Iron or Aluminium. The Ali is higher compression than the cast. Both types of C7RA heads are Higher comp. than the C81T heads.
The manifold required has the facility to fit two sets of 3 carb mounting studs.
on its carb mounting face.

[Wayne Hingley]

I think if the pulley in the top of this photo was flipped around (so the cone-shaped portion is close to the engine), the belt would be more aligned with the crank pulley and generator.

[super dave]

I do not believe that the pulley can be reversed but I will see if I can get the part number off of the one I pictured on my next visit. Yes the carb can be mounted either way I did not know which way at the time I ran it up.

[Lynn Eades]

I don't have any answers, but the water pump looks fine.
The fault has to be in the area of the crank,crank pulley.
Rick, which crankshaft and block are listed in your parts book?

[Richard Coutts-Smith]

Peter, thanks for the ID on the map case. I have been using one for the last few years (for our bush trips) and always wondered what/how the brackets fitted.
See quite a few of these around over here, all in unused NOS condition. Remarkable for a bit of kit that age (C.G. Hartley & Co. 1944), any idea what the fancy hook on the top strap is for?
Rich.

[Mike Cecil]

The fancy brass hook on the Australian version has a swivel base, and is for hanging the case from the belt when dismounted, leaving the hands free to work the map, chinagraph pencils, etc.

The Lynx was not the only vehicle to be quipped with the mounting points for that particular design of map case: The Australian Cruiser tanks were also so equipped (underside of turret roof in easy reach of the CC) and I seem to remember that some other Aust AFVs were similarly equipped, but I'd have to go searching for the exact references. Is it a British design that also equipped British AFVs? Perhaps our MLU Brit armour enthusiasts can enlighten us, please.

Most of those map cases I've seen available through disposal stores in Australia had the hook removed by cutting the strap. I remember having to search quite a few before I found a couple that were still intact.

Mike

[Richard Coutts-Smith]

Thanks Mike, I thought it looked like a belt hook, but also thought it was too impractical for that, always nice to have these niggly little questions answered. Sounds like the contract for the map cases way exceeded the amount of vehicles needing them.
Rich.

[lynx42]

Originally Posted by Lynn Eades

I don't have any answers, but the water pump looks fine.
The fault has to be in the area of the crank,crank pulley.
Rick, which crankshaft and block are listed in your parts book?

Hi Lynn, Probably not much help but the numbers are straight out of the book and don't mean much to me.

Block .. .. .C29SR 6010 S.
Crankshaft .. . . C99A 6303.

The water pumps on mine are single belt not double like Peters.

Crankshaft Pully.. .6312.

Water Pump Nos... .... RHS. 8503
Water Pump Nos... . LHS. 8504

Water Pump Pully. ... 8509

Regards Rick.

[Andrew Rowe]

The block that Peter has appears to be a 1946 model from my information that I have. If I read the numbers right ; C59A block is 1946 , stating that the crankshaft is long and high pressure oil pump used. Model C59T is a 1946 , same as above but uses high torque cam and heavy duty exhaust valves. These configurations are what came from the factory originally, but you can build most of these flatheads up from many assorted parts, and most are interchangable. The crankshaft used in the C59A and C59T blocks is a 99A-6303 , using high pressure oil pump ( 65-70 lbs ) There are about 6 types of crankshafts used in the common types of flatheads, but I thought they were all bascially the same length.