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Engine basics => Engine set up tips => Topic started by: Terry Caron on May 04, 2015, 03:43:18 PM

Title: Forster glow engines - ? oil
Post by: Terry Caron on May 04, 2015, 03:43:18 PM

Hi all -

I recently acquired a nice Forster .35 and, on 8% nitro/28% castor fuel, it starts cold in 3-4 flips, hot starts in 1-2 and turns a 10-6 APC to 11.3K.
While I'm happy with the way it runs, I'm just wondering if Forsters need that much castor.
Anyone know what oil content they recommended?

Terry

EDIT:
I found a copy of the factory instructions specifying 25% castor for these engines.

Title: Re: Forster glow engines - ? oil
Post by: Robert Zambelli on May 04, 2015, 07:48:41 PM

Terry - I have quite a few Forsters - 29, 33, 35 and 99. Both lapped and ringed.

I run ALL my vintage engines - Fox, McCoy, K&B, ETA, Atwood, etc -  on Brodak 10-23, 50/50 castor/synthetic.

Never had a lubrication issue.

   Bob Z.

Title: Re: Forster glow engines - ? oil
Post by: Terry Caron on May 05, 2015, 07:06:46 PM

Thanks Bob - good to know.
Less castor = less mess, right?  ;)

BTW, if you (or anyone) have disassembled a Forster, will the rod/piston come out the front a la O&R or must the head come off?

Terry

Title: Re: Forster glow engines - ? oil
Post by: frank mccune on May 25, 2015, 06:18:15 AM

     Hi Terry:

     I read your post and had to think about it for a brief period of time.  What I came up with was:

     1. Your present fuel appears to be doing a great job so why change?

      2. If the manufacturer suggests a certain fuel, why not use what they recommend?  They know more about the engine than anybody on this site. Lol

      The rpm figures that you are getting are very good for an engine from that era.  Do not burn up this engine attempting to make it do what it was not designed to do. Enjoy what you have.  Can you say 4 cycle only? Lol

     Again, thanks for the needle valves.

                                                                                           Stay well my friend,

                                                                                           Frank