MTFCA Forum

Posting this for a member in Australia. Chris

I'm in Australia and just bought a lovely 1915 Speedster. It has a Type A RAJO head (two rocker covers)

I am having trouble sealing the rocker covers to the head to stop oil leaks. I can't find seals on line.

Can you advise where I can buy seals?

Jeff Brown

Pretty sure those two covers are a fantasy item. I made the patterns 20+ years ago and sold lots of them. The original valve cover Rajo supplied was one piece, open at the back to clear the dash. I’ve never seen an original , but likely there are some out there. Using one of those sure will not help your excess oil issue.
The way to use these is to have an oil soaked thick felt pad inside on top of the rockers. A heavy oil supplied to the felt on occasion keeps everything lubed well enough. If you are getting a lot of blow by, perhaps fitting some valve seals will help. I’m afraid you are likely on your own if you want to seal them up better. Maybe clean them well, and apply a bead of good RTV sealant, let them dry and the reinstall. Otherwise , cut some thick soft rubber for gaskets and try that.

The Rajo 4 valve (model A) head did not have any seals. The original valve covers was a one piece unit that did not even have a back to the valve cover. The rear was totally open to clear the original style coil box porcelain wire terminals. There is no drain areas cast into the head so they are just a messy/oily head assembly. I use a heavy weight oil on the rockers and pushrods and also the intake valve stems. Then I run the engine for about a minute. Then the only thing you can do is use a rag to wipe up the excess oil. Langs sells a thick piece of felt that can be soaked in oil and put in the valve covers to help with the oiling of the rockers. If you have an aluminum head and are running the 2 separate rocker shafts I highly suggest to replace the 2 single shafts with a single "long" shaft to keep the rocker towers from rocking front to rear as the valves are opening. The rocker towers have been know to wear the head surface from the towers rocking back and forth. Then the only way to use the two single valve covers is to cut a notch in the covers to clear the single rocker shaft when installing the covers. I believe the 2 single covers was an attempt to help the rockers towers not to rock back and forth with the 2 single rocker shafts.?? If you notice, the 2 single covers are very heavily made. The two single valve covers is a fantasy item that came with the reproduction 4 valve heads that were made in Australia. The 2 single covers are a new item that did not come with original heads. The repro heads were either cast iron or aluminum. I have both styles of covers (single long original cover, and two single covers). I plan on using the single cover since I have a single (long) rocker shaft.
If you wanted to try and seal your covers, you will have to make your own seals out of neoprene/rubber or maybe even felt.
If you have any specific questions about the 4 valve Rajo head, let me know. Good luck with the project......

have fun and be safe .....

RE the blow back; While mine is a Chevrolet head conversion it suffered the same thing, or I should say I did before I got a valve cover! When I did fine one, I slit fuel line and installed along the bottom of the cover, which did cut down on oil splatter. The first tour I did before the cover in my Huckster, there was an oil splatter outlining my body on the back of the cab wall.

I have several Fronty heads and the valve covers leak oil and make a mess. Gaskets are not and were not available for Rajo or Fronty's.

So I used Mechanica silicon sealer and placed a bead just inside the rocker cover. I made 1 pass around the head and then after the sealer set up, I added a 2nd bead on top of the 1st bead. This becomes a coffer damn and keeps the oil from running down the sides of the head and block. It works on my Fronty's and my '28 Chevrolet ohv sprint car with an aluminum valve cover. Quick and easy and relatively inexpensive.

frontyboy

Thanks for the comments about sealing my RAJO head.

Thought you might like to see the unusual oil delivery mechanism and the seal I created from a rubber extrusion.

a second image

Took me a while to see where the T intake was connected! At first I was seeing the T exhaust and intake was was trying to figure what the was connected to the head.

Nice work Jeff, seals and simple!

drjefb@tpg.com.au wrote: ↑

Thu Jun 18, 2020 8:40 pm

Thanks for the comments about sealing my RAJO head.

Thought you might like to see the unusual oil delivery mechanism and the seal I created from a rubber extrusion.

I would be interested in the material that you used. What was it originally. I’ve looked at similar at hardware store but it’s too large.

Sort of off topic but I'm new to the forum and don't know how to post a New Topic. I recently found a 4 valve Rajo in excellent condition just missing the valves. Am I supposed to user the existing valves in the block? If not what size are they. In addition what pushrods can I use?

Mike
With a little digging you can buy just about any pushrod you can imagine new.
Head gasket for the 4 valve. I can probably help you as a few years ago I did a production run of these in copper shim and still have the digital file. People seemed to be satisfied with them. I don’t personally own a 4 valve.
The valves. Talk to your automotive machine shop, they can probably help you. Maybe someone will provide a part number.

I overhauled a 4 valve RAJO years ago... seems to me it was a big block chebby exhaust valve dropped right in

Great solution, Jeff. Friend Jarvis saw this thread and sent me these. With his permission, I am posting. It shows very nicely the original open back valve cover. Back then they didn’t care a ding dong about a little oil spray.

Thanks for the info.

Alright guys, I've been following this thread mainly because anything that's posted with the Rajo title in it I have to check out, and watching this one, I just kept thinking, most of you are going with the wrong solution. As some of you know I'm more of an era guy and just love stepping back in time and doing what they did back in the day, so what I have to say doesn't work for a lot of you. Different strokes for different blokes, it's okay. But why go to all the trouble with so much oil to the rockers. I don't have a messy oil soaked exterior engine due to my Rajo B Head, other than the normal "it's a Model T "oil seepage here and there. Been driving old #4 for 52 years and during that time as far as rocker maintenance have only replaced one rocker arm (at the rear) period. All I have underneath the valve cover is a felt pad laying on top of the rockers. Before I start the car, and I only do this once a day no matter how far I'm going to drive, I remove the cover, lift the pad, oil each rocker, at the shaft, then valve side and push rod side. Then lay the pad down and run a small stream of oil all the way down the center front to rear and then across push rod side to valve side and I'm done for the day. The old timers used to tell me I was overkilling. At best they used to do it like once a week or every few days when ever they got around to it. I realize that some of you don't want the hastle of having to do that bit once a day but I sure don't have the messy oil problem and haven't had other rocker maintenance stuff due to excessive wear . Ed aka #4