View Full Version : F engine Good & Bad

Air Randy
08-13-2010, 01:52 PM
Bad - I bought the 74 FJ40 Blue Mule with a F.5 motor in it that is only 239 cu.in. and didn't run :o

Good - I installed a JimC Aisin carb and was able to get it to run :thumb:

Bad - It had no power, low compression and badly worn cam lobes :(

Good - I did a valve job, installed new rings & bearings but decided to do the cam another time :)

Bad - Compression improved, no smoke, but still marginal power :confused:

Good - Installed new HEI distributor, performance improved a little :)

Bad - Had to set timing @ almost 30 degrees static to get it to rev up, wrote this off to the rounded off cam lobes, no power at all on the street :(

Good - Drove it like this for almost 18 months, did fine off road, good torque :p:

Bad - Got tired of not being able to drive it on the street due to no power:rant:

Good - Ricardo helped me and we got a new cam installed this week:cheers:

Bad - New cam helped it run much smoother, lifters can now be adjusted correctly, but only a small improvement in performance and timing must still be absurdly advanced :confused:

Good - New cam increased the oil pressure by 10 psi across the rpm range and we cleaned an unbelieveable amount of coked up crud out of the side cover/lifter valley :thumb:

Bad - Due to the increased oil pressure I now have oil leaking from the dreaded oil galley plug near spark plug #5 in the head :banghead:

Good - The new valve cover, side cover and timing cover gaskets dont leak :cool:

Bad - I shamelessly plugged the oil galley hole leak with JB Weld for now :hill:

Good - While waiting for the JB Weld to set up I took off the top of the HEI distributor ;)

Bad - When I removed the internal rotor cap the mechanical advance arms and weights fell out into my hand since both mounting posts were broke off :mad:

Good - Now I know why the timing was always goofy and I wasn't getting much performance because I was getting almost zero timing advance :o

Bad - Now the Blue Mule is out of service until I get a functioning distributor :(

Good - I called DUI distributors and even though the unit is 1 year out of warranty they are going to repair it for me for just the cost of shipping :thumb:

Such is the life of an F engine owner. :D Hopefully once I get a properly functioning distributor in it I will be able to drive it on the street. :thumb:

Has anyone done the job of drilling out the oil galley plug and tapping it while the cylinder head is on the engine? I read all about how to do it on MUD, just wondering if anyone else has had the pleasure. Oh, and if you have an angle drill I'll probably need to borrow that from you.:thumb:

08-13-2010, 02:11 PM
I don't know if the F head galley plug is like that on a 1980 2F, but I drilled and tapped mine (I think I used a 1/4-20 tap). It was super easy - I used a DeWalt 18v drill (not right angle) and the cast iron was very easy to tap. I tapped it quite deep, fired up the engine to let the oil push the crud out of the hole, and then cleaned the threads of oil, gobbed it up with JB-Weld, and inserted a hex allen screw. No drips, no runs, no worries. The hammered-in aluminum plug from the rebuilder was very cheesy and didn't fit tightly - it was pathetic.

The 2F galley plug is angled toward the firewall, but I had no access problems to speak of with my bulky rechargeable drill.

08-13-2010, 03:03 PM
Wowsers - not good to have distributor parts fall into your hands. It is good to know that DUI is stepping up and taking care of you. Hopefully it won't take long for the repaired distributor to get back. Have you considered popping in a points dizzy in the interim?

Glad to hear there are no leaks, especially on the timing cover. Sorry to hear about the head plug. On my F.5 engine I thought about, but didn't replace the plug. Perhaps after you get through yours, we can do mine.

08-13-2010, 03:07 PM
I have one of these you can borrow.

08-13-2010, 03:57 PM
Wow Randy, that's quite a story :-)

Yep, it is tough to get much power without the spark at the right time. I run the pre-1968 "Non-USA" vacuum advance distributors, and they work great with the ported Aisin carb. I had Jim Chenoweth build it. He added the port, and also tweaked it special to run better at my elevation. I've had it on there for over 10 years now and it's getting to be about time for another rebuild though.