acmoc

ACMOC Membership Benefits

  • FREE quarterly magazine filled with content about antique Caterpillar machines
  • FREE classified listings
  • ACMOC store discounts and specials
  • Full Bulletin Board Access
    • Marketplace (For Sale/Wanted)
    • Technical Library
    • Post attachments

$44 /year ELECTRONIC

$60 /year USA

$77 /year International

Fuel in oil

More
2 months 3 weeks ago #239143 by Quadrajet2000
Fuel in oil was created by Quadrajet2000
Guys I'm working on a 1971 Cat D5 96J with either a 333C or 3306 engine?  Anyway my problem is I'm getting a good bit of fuel into the crankcase oil to the point oil no longer has viscosity and started blowing a fuel/oil mix out of the vent tube at high rpm so I shut it down.  Engine does not miss, crankcase blowby is very minimal, exhaust smoke was normal and oil pressure was actually still in safe range.  It was however extremely hard to get started the last couple times due to the pump loosing prime.  So do I start with rebuild on the injection pump alone or it and the lift/transfer pump?  
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago #239144 by Rome K/G
Replied by Rome K/G on topic Fuel in oil
Start with inspecting/rebuilding the transfer pump.
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago #239146 by Old Magnet
Replied by Old Magnet on topic Fuel in oil
1971 would still be a D333C with compact scroll pump and conventional transfer pump. Are you seeing fuel coming from the transfer pump tell-tale drain line (make sure the line is not plugged). Candidate fuel to oil leak sources are transfer pump seals, problems in the injection pump and over fueling injector capsules. The usual suspect fuel filter tower to injection pump seal would leak externally if the sealing was a problem.
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago #239184 by Quadrajet2000
Replied by Quadrajet2000 on topic Fuel in oil
Haven't had a chance to mess with it yet but it looks like a greasy mess around the transfer pump so it's very possible.  I'm hoping it's not my injection pump $$$ but not sure how much I trust it either though.  
Attachments:
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago #239198 by Quadrajet2000
Replied by Quadrajet2000 on topic Fuel in oil
  Done some investigating today. I'm gonna assume the pipe plug is not supposed to be on the bottom of the pump?
Attachments:
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago #239199 by Rome K/G
Replied by Rome K/G on topic Fuel in oil
Your correct!!!!
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago - 2 months 3 weeks ago #239200 by Old Magnet
Replied by Old Magnet on topic Fuel in oil
I'm thinking that's the tell tale drain line connection that's meant to drain off any transfer pump seal leakage and yes it should be at the bottom of the pump but should have a drain line attached instead of a plug. With the drain plugged any seal leakage has no where to go except into the main engine sump.
 
Last edit: 2 months 3 weeks ago by Old Magnet.
The following user(s) said Thank You: Fat Dan

Please Log in or Create an account to join the conversation.

More
2 months 3 weeks ago #239201 by Quadrajet2000
Replied by Quadrajet2000 on topic Fuel in oil
Thank you all for the help. I now have a good place to start and yep it leaked fuel when I pulled the plug out. I really love running the little Cat she just needs a little work.

Please Log in or Create an account to join the conversation.

Time to create page: 0.142 seconds
Go to top