hsukaria

I was thinking more for modern-day engines, if somebody were to start a new design without legacy constraints, for a ringed engine.

Sport_Pilot

But that would be a poor choice because most glow engine customers want ABC engines.

hsukaria

Depends on the displacement, I was thinking about 15cc engines range.

Sport_Pilot

Well the Saito's are built that way. Possibly the newer OS as well. I don't see it as an improvement however. Just another way of building them. Both methods can result in a light engine. Most smaller glow engines weigh more because of the brass ABC sleeve.

BTW high nitro engines need to clamp the head to the block. When nitro detonates it can break the cylinder to head connection and then the head becomes a missile.

carlgrover

I didn't see a whole lot of Fox engines for sale at the Perry swap meet this Spring. I bought the only Fox .25 there (NIB). I was also lucky enough to get a Fox .45 about a year ago when they were making the last iteration of that engine with the new carb on it. It's much better than the older carbs with their coarse needle adjustments. I have never seen a new generation Fox engine for sale at a swap meet.

Like most here, I would have bought several new ones if I had known they were going to quit making them. I always wanted a .60 or .74 and never got one.


carl

hsukaria

I would swap my used 74 for a 45. I have no use for a big 74. My 74 has the EZ carb though (older).

Cougar429

My Feedback: (3)

A few months apart and from different estate sales, but I was lucky to find a pair of NIB Eagle IV 60's. I figure those are about as large as I want to go 2-stroke.

hsukaria

The 74 is the same size externally as the 60. Biggest difference is the 74 is higher compression.

Cougar429

My Feedback: (3)

Fuel burn is likely higher, as well. If I need something swinging a larger prop would opt 4-stroke.

hsukaria

The expectation is for the 74 to swing a bigger prop, but compared to modern-day engines, it is not a big prop swinger, more of a higher speed and power at WOT than torqaue. It is more prone to overheating than the 60 if not careful or using the wrong fuel.

spaceworm

Higher compression of 74 MAY dictate using FAI or 5% nitro fuel to avoid overheating. Higher compression and nitro MAY cause plug failure.

hsukaria

Yep, been through all that. Running 5% nitro MAX on it. It also ran well with 0% nitro. I replaced the head button with the latest from Fox and added 2 head shims to help reduce heat issues. I had experienced plug failures before the head button and shim changes. Otherwise, it runs fine.

flynal

Ok guys how would I find an abc piston and liner for an 60 eagle 4.i was flying a new in box one after some break in on the stand and something went threw the engine.i don't know if it picked it up on take off or if engine metal went threw.i had four flights on it and was running damn good.thanx in advance.ps been following this thread for along while and inspired me to get a couple of foxes.

Cougar429

My Feedback: (3)

Can you post a pic with the head removed? I had mine burn the back off the piston on the first flights. Warranty repaired by Fox and they included a pair of new head designs for that one and the second.

flynal

Do not know how to post pics but there is a groove in liner and a matching one in the piston from intake port to top of piston,on the back side.the engine still runs but whey down on compression and power.i did not buy from fox but from eBay.it is a late production because it has the last carb they produced.will fox still repair?i can't even find there web site anymore.anyway thanx for the reply and maybe I will try to call them,can't hurt.wouldnt mind changing it to ringed if possible.al

1QwkSport2.5r

Chances are the wrist pin clip broke and fell out. Common problem on Fox engines. Good luck finding new parts. Look on EBay. For the price, you might be better off finding a different engine to use in the interim.

hsukaria

The wrist pin might be a problem when messed with, but I doubt flynal touched it. I haven't heard of many people having wrist pin problems if they are not touched. He said he bought it NIB, but from Ebay, you have to wonder.

flynal

I did check that the wrist pin and keeper were still in there,and they were.i had that thought also ,the groves were lined up with the wrist pin hole. I am sure that it would be cheaper just to replace it with something else but I wanted to operate a piece of American history.any body need some parts most are almost new? Al

Cougar429

My Feedback: (3)

On the bottom of the page will be a "Go Advanced" tag that will allow you the option below the text of uploading pics from your PC and changing so that you get a notice of new posts on this thread.

I may be able to make use of that new version carb. Not sure if I have that one on either of mine and one reason pics might help.

1QwkSport2.5r

The problem is the little tang breaks off usually. I had it happen on a Fox .40 twice. I've read several posts in the past on other forums of the G clips breaking off and snagging in a transfer port and taking out the piston and liner.

spaceworm

It used to be standard practice to go ahead and break off the tang after installing the clip. Insures it not doing so later.

Charley

My Feedback: (2)

Play hell getting it apart later.

CR

hsukaria

Cougar, there is a good picture of the new carb in post #4138. Great carb. I wouldn't mind getting another one if available. I wish I had bought extras when Fox was still selling them.

spaceworm

A sharp scribe under one edge of the clip will free it. Better to take it apart because you want to, rather than because you have to.

1QwkSport2.5r

I've never heard of that before - not to say it's not a bad idea. I have only encountered this problem with the one Fox engine.