Dear fellow members.

Hope that somebody can give me an advise about a problem that is keeping me out of the roads with my M2 1928 Rugby touring 4 cylinders.

The story started two years ago when the cranckshaft broke. Fortunately found a spare and went to an old mechanic that put the car on the road again fixing things old style. The result was that the engine did not show oil pressure at all and was “marking the territory” all around consuming abnormal amount of oil.

Following some advises, decided to “make” the engine according new technology. Crancksaft was magnafluxed, and balanced, new cylinders were machined in, new pistons, new valves, new metals, etc. etc. and everything was machined with tolerances. The engine was assembled and torque given to the head. Everything looked like a beauty.

Installed in the car started nicely with no vibrations with a pleasant rum rum at very low speeds and releasing horses when pressing the accelerator.

But… some water leaks appeared between block and head, even though retorqued again when hot and the following week.

Investigating found that torque given to the nuts of the head studs was not correct as the nuts locked in the studs making the assy work as a bolt.

Solved the problem and with new joint engine started again nicely but leaks continued even nuts where tightened with up to 8 kgms torque according manual sequence, hot and cold after several nice runs summarizing more than 100 kms.

Decided to put a new joint but sealing critical points.

When disassembling found in cylinders 3 and 4, ½” of water after a week without using the car. So, cleaned everything, installing a new joint in this case, sealing around studs and water passages with high temperature sealing compound.

Filled cooling system and found not exterior leaks, but after 24 hs, looking and investigating through spark plug holes, found that 2 and 4 cylinders had water again.

Thanks

Ricardo

Do You own a car built by Durant? 1928 M2 Touring

After reading what you have done to correct the leaking problem, this would be my next step. Dismantle the head, clean both the mating surfaces thoroughly, and then using a suitable straight edge, check to see that both surfaces are flat. I would venture a guess the head surface could be a fault and automotive engine rebuilders will have this tool to check flatness. If it is out of tolerance, they can machine it flat. I would look carefully on both mating surfaces and cylinder walls for possible hairline cracks that may have developed in the leak area. Another thing to consider doing is: run the proper size die on the head stud threads and retap the head nuts to aleviate any thread binding so to ensure the proper torque is being applied to the head. Lastly, I would follow torque sequencing specs used for that particular style of engine.

Do You own a car built by Durant? 1928 D75

Ricardo,
I totally agree with S. Blomquist's answer and can add something more.

I had exactly the same problem and tore an MG four cylinder engine down 3 times. Like you I could not find a problem, but it still leaked even with New Gaskets each time. But IN A TECH Manual I found that the STUDS had PULLED-UP the last 2 or 3 threads up from the block, causing a slight mound around each stud!! The fix was to pull the studs, flatten the "mounds" by having the "Block Decked" slightly then "champfer" or undercut the stud thread holes in the block to prevent this happening again! Finally I found that the head was warped. Actually by running it, getting it hot, then having the leaking problem, it had probably warped more. I had the Head machined also and No More problem.

Likewise it is possible you have a cracked block that only "opens" under running or "heated" conditions...but because you have two cylinders leaking water so I would rule that out.

The final coment on retapping Nuts and using a die on the Studs was good too. Try using a light oil or an Anti-Seize compound on the threads (for accurate Torque readings). Lastly use hardnened Flat washers under the Nuts (to prevent binding)while using the correct Torque settings (in 3 stages). This should cure your engine problems.

It worked for me and hope it helps you too.
Lance C.

Do You own a car built by Durant? 26 Locomobile JR-8 Sedan and 26 JR-8 Roadster project, 30 Durant 410 Special Deluxe 4Dr.

Unless I missed it in the answers to your problem, one other thing I would do is to replace the studs and nuts with modern hardened/heat treated studs. The old studs might be stretching the threads and not keeping the proper torque settings. I did this to my engine and after proper torquing, I checked stud torque and it stayed put.

Do You own a car built by Durant? yes 1930 Durant 614 sedan

i have had no experience on durants with this but i would include checking hole depth to be sure a stud and nut tightened are not "bottoming out " if the unit is too long....if that is possible...or do the stud holes have no bottom????....regards gary k

Jim, et All,
Good catch on the STUDS, which may have Streched-out (especially if over-torqued) and are no longer holding the head tight to specs.

I thought about this last night and was going to add it this morning but you had already, Good catch!

I have used "ARP" brand fastners and Studs on Chevy and Ford engine rebuilds and they are of excellent quality. They are sold in sets and are not too expensive...especially considering the cost of a rod or main bolt failure; i.e. Total engine destruction!
Available from "Summit Racing" and other high performance auto catalogs.

These older engine Studs could probably easily be matched with modern studs and fastners of the right length and size.

Lance C.

Do You own a car built by Durant? 26 Locomobile JR-8 Sedan and 26 JR-8 Roadster project, 30 Durant 410 Special Deluxe 4Dr.

Agree with all of the above, especially the stret ched head studs and the mound pulling up from the head surface with the solution of chamfering this area. ARP makes excellent hardware, nothing wrong with using modern technology in this critical area. Would using a coolant dye help in narrowing down where the leak appears?

Do You own a car built by Durant? 1930 6-14 standard coupe

Dear Fellow members:

First of all I want to point out the extraordinary response of so many friends, ready to cooperate. We should be very proud about the Club we belong to.

I will have a bussy weekend this week, working on my Rugby following the advises. First of all disassembling and inspecting.

Regarding the studs and nuts, I did not mention before, that have been done according measures following updated technollogy, unfortunately originally have not been cleaned thorougly the threads of the nuts, that retained remainings of the heat treatment.

Hope that next week can give you some more information of what I find.

Thanks again

Ricardo

Do You own a car built by Durant? 1928 M2 Touring

Still with problems eventhough changing joint type, use of sealers, no monds, sliding joint, no cracks, and following almost all advieses.
Last advise is to remachine cylinders head. Found some distortion in the centre that looked minimal, but may explain the water leak. Hope that the block should not be remachined.

Best regards, thanks and Happy new year.

Ricardo

Do You own a car built by Durant? 1928 M2 Touring

Ricardo,
If you ran a Straight-edge over the block deck and still could not find any gaps around the stud-holes (using a Feeler-Gauge). These (gaps)would be caused by "Mounds" from the last 2-3 threads pulling up from the stud-holes.

Then if the Block Deck surface is perfectly flat. So it is probably the head that is "Warped" as you say.
Machining the Head flat should end your water leak problem with a Good head gasket and sealent.

Happy New Year 2009,
Lance C.

Do You own a car built by Durant? 25 Locomobile Brogham, 26 Locomobile JR-8 Sedan and 26 JR-8 Roadster project, 30 Durant 410 Special Deluxe 4Dr.

The best and easiest way to find out were your block and head is distorted is by
using blue layout die spray and apply a thin layer on head and block.
take a precision straight edge and drag it over both surfaces in a criss cross pattern.
This will show you the high and low spots.
Unless you have a honing stone the size of the surface of you block it is ver difficult to get a good surface finish.
Good luck
Franz

Dear advisers. Finally remachined cylinder head and eliminated water leaks. Used a German product called Curil to paint joint both sides and followed manual torque sequence.

Still have not clear why had the distorted head, as it has been machined before assembling the engine. My options are:
a) was not well machined originally when repairing the engine
b) was distorted due to heat elevation when leaking water reduced the water level (Motormeter did not show temperature increase)
c) Incorrect original head tighting when nuts blocked to the studs produced not only water leak but also contributed to distort the head.
Probably will never know the answer but the experience teached me a lot and evidenced how strong support can be obtained from club members.

Thanks

Ricardo

Do You own a car built by Durant? 1928 M2 Touring