Gas Engines Questions or comments about gas engines can be posted here

Gas ST 3000

Reply
Old 09-23-2012, 12:00 PM
  #1
voodoodb
Thread Starter
 
voodoodb's Avatar
 
Join Date: Jun 2002
Location: Flora, MS
Posts: 532
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Gas ST 3000

Need some help. I have a ST3000 that was professionally converted to gas with Electronic Ign. It has a new rod with roller bearings, and the crank has been hardened. I'm running a walbro carb and 40:1 mix gas with Synthetic oil. The engine is mounted inverted. My problem is this thing runs great but is as messy as a glow engine. It leaves a trail of oil from the firewall to the tail. Is this just the engine or do you think there is something else. It is not rich, as I said it runs great from idle to full throttle. It's just the mess. It seems to me that the oil is either being sucked out of the carb or leaking from the head/cylinder mateing. I have tried a velocity stack of about 1/2" long but it did not make a difference.

Also there is a bronze or brass shim between the head and the cylinder. If I take that out will I gain any power? I took it out and it turns over freely, but I have not tried to run it without it and don't want to mess it up.

Thanks
Doug
voodoodb is offline  
Reply With Quote
Old 09-23-2012, 04:31 PM
  #2
captinjohn
 
Join Date: Jan 2002
Location: Hesperia Michigan, MI
Posts: 12,887
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

I would not remove the copper gasket...unless it is leaking. You do not need higher compression ratio for gas. You may want too install a Frank Bowman ring that breaks in faster and will leave less oil on your airplane. If the ring is on the hard side...your engine may take a long time to break-in.

Good Luck Capt,n
captinjohn is offline  
Reply With Quote
Old 09-23-2012, 04:34 PM
  #3
voodoodb
Thread Starter
 
voodoodb's Avatar
 
Join Date: Jun 2002
Location: Flora, MS
Posts: 532
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

Thanks Cap'n, it does have a Bowman ring on it.
voodoodb is offline  
Reply With Quote
Old 09-23-2012, 04:40 PM
  #4
captinjohn
 
Join Date: Jan 2002
Location: Hesperia Michigan, MI
Posts: 12,887
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

That oil getting on the airplane may go away to a less bothersome degree. Maybe you can come up with a slight change in exhaust too help keep oil off the fuse. Good Luck, Capt,n
captinjohn is offline  
Reply With Quote
Old 09-23-2012, 05:24 PM
  #5
voodoodb
Thread Starter
 
voodoodb's Avatar
 
Join Date: Jun 2002
Location: Flora, MS
Posts: 532
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

The oil is not come ing out of the exhaust. It is either being sucked out of the carb or leaking from the head.
voodoodb is offline  
Reply With Quote
Old 09-23-2012, 05:39 PM
  #6
KenLambert
 
KenLambert's Avatar
 
Join Date: Dec 2001
Location: Livingston, TX
Posts: 868
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

Some of the tigers have a oil port going to the front crank bearing and the groove goes a little to far and will cause it to leak running gas , you can replace the bearing with a double sealed one and it will stop
KenLambert is offline  
Reply With Quote
Old 09-23-2012, 05:42 PM
  #7
captinjohn
 
Join Date: Jan 2002
Location: Hesperia Michigan, MI
Posts: 12,887
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

Clean up the entire engine & run it again for a little.The leakis not the carb (my opinion) but could be the head gasket or front seal.or exhaust joint. You should be able to tell where the oil leaks...starting with a clean engine. You may check the head gasket....check for damage, and if it looks ok clean it super clean and coat it with clear shellac= 2 coats. reinstall and torque the head in a chris/cross pattern.
captinjohn is offline  
Reply With Quote
Old 09-23-2012, 06:16 PM
  #8
captinjohn
 
Join Date: Jan 2002
Location: Hesperia Michigan, MI
Posts: 12,887
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000


Quote:
ORIGINAL: KenLambert

Some of the tigers have a oil port going to the front crank bearing and the groove goes a little to far and will cause it to leak running gas , you can replace the bearing with a double sealed one and it will stop
Ken is the man for Supertiger engines. I got a chance to meet him at his workshop..very impressed what this man can do. I think I visited for a couple of hours, and really enjoyed it. Take Care Ken, looks like we replied about the same time.
captinjohn is offline  
Reply With Quote
Old 09-24-2012, 04:55 AM
  #9
voodoodb
Thread Starter
 
voodoodb's Avatar
 
Join Date: Jun 2002
Location: Flora, MS
Posts: 532
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

Yes, Ken did the conversion on this one. I'll clean it and do as y'all say. I am 100% sue the oil is not leaking from muffler gasket. The oil is on the front fins of the cylinder and goes on the firewall then down the belly of the plane.
voodoodb is offline  
Reply With Quote
Old 01-07-2013, 09:01 AM
  #10
Iflyglow
 
Iflyglow's Avatar
 
Join Date: Oct 2002
Location: Clintonville, WI
Posts: 3,843
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

Is Ken still doing engines? I have sent emails and not received a responce.
Iflyglow is offline  
Reply With Quote
Old 01-09-2013, 11:56 PM
  #11
KenLambert
 
KenLambert's Avatar
 
Join Date: Dec 2001
Location: Livingston, TX
Posts: 868
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

I still do engines, I will admite I have been slow on replys been really busy but things are slowing down it is that time of year trying to beat all the new copay's. Plus my wife just had back surgery so I will get back to everyone.
KenLambert is offline  
Reply With Quote
Old 01-10-2013, 04:16 AM
  #12
voodoodb
Thread Starter
 
voodoodb's Avatar
 
Join Date: Jun 2002
Location: Flora, MS
Posts: 532
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Gas ST 3000

Glad your back Ken.
voodoodb is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 05:11 AM.