really bad gas mileage

a77fj40 · 05-22-07, 09:49 PM

Hello all,

I am new to both this site and the world of Land Cruisers. I have wanted one forever and just recently found the FJ-40 of my dreams.

I have a bone stock 1977 40 and I have a question for all of you about fuel economy. Now, i know that this is a 30 year old, carbureted engine pulling a 5000 lb vehilce but 7 miles per gallon seems low to me.

What kind of mileage are you guys getting and can you think of anything that could be causing mine to be so low?

Thanks in advance.

db

badass · 05-22-07, 09:59 PM

First off, you might need a carb rebuild, also a tune up is probably not a bad idea. Just don't expect to get much better than 11 mpgs depending on mods.

cardinal fang · 05-22-07, 10:00 PM

Yep, that's about what I get. 8 most of the time, but I am running 37" MTRs with a SM420, so that may be the reason.

fj40forlife · 05-22-07, 10:09 PM

I know I didnt get that bad when I drove mine in the street. Check for stuff like oil, filter. gas filter and blah.

n2666s · 05-22-07, 10:24 PM

get the carb rebuilt and the dizzy rebuilt; JC did our fj60's and we went from 9 MPG to 16-17

Lou

85roktoy · 05-22-07, 11:10 PM

The dizzy???? Sorry, newb confusion!! Distributor??

mrmouse88 · 05-22-07, 11:12 PM

Hate to make you guys feel bad, but im averaging 18-20 miles to the gallon(cdn)

yotawheeler · 05-23-07, 01:47 AM

yea...im a bit lower then mrmouse but i think i was getting in the ball park of 15 or 16 before i left...i had swaped over to a pentronix kit instead of the points ignition and also had a buddy tune up my carb for me...

crazylandcruiser · 05-23-07, 02:20 AM

change from points to electronic and also send your carb to jim c he works magic and will make your cruiser run like a dream!

Clyde-2 · 05-23-07, 06:24 AM

As Crazylandcruiser said, switch over to electronic ignition and also set your timing. My mpg went from about 8 to 12 when I switched to electronic dizzy.
FYI, a bone stock 40 weighs around 3200lbs depending on your mods.

JohnnyC · 05-23-07, 08:24 AM

remember if you are running larger tires you have to take into account the odometer being off...my 33" tire are off by 1 mile per 10...this will give you almost an extra mpg to your # soooo you are getting 8 mpg....wait ....that still sucks....wait... i get that also

...how many miles on the rig?

my rig has over 435,000 miles on it...8 mpg...maybe not that bad after all

LOL

'74 UA FJ · 05-23-07, 08:50 AM

Quote:

Originally Posted by badass

First off, you might need a carb rebuild, also a tune up is probably not a bad idea. Just don't expect to get much better than 11 mpgs depending on mods.

Badass, what would you do in a tune-up? Just wondering.

a77fj40 · 05-23-07, 09:41 AM

Man you guys are awesome! i just posted this last night and there are alredy all of these replies.

Just for clarification:

Dizzy is an electronic ignition system to replace the stock points?

Who is Jim C?

mrmouse, how are you getting such good mileage?

The plate in my drivers side door jam says GVWR(Gross Vehicle Weight Rating) is 4950lbs. Is that different from actual weight?

JohnnyC, i have 111300 give or take on it and 29" tires which i think are stock??

Thanks again guys. This place is great.

db

JasonH · 05-23-07, 09:50 AM

Dizzy is just our lazy way of saying distributor.

Jim C is Jim Chenoweth, one of the Cruiser carb gurus. Mark Algazy is another.
fj40jim@aol.com and http://www.marksoffroad.net/

mrmouse uses those wierd Canadian gallons.

GVWR is the vehicle weight plus the maximum weight you can load in it - passengers and cargo.

29" is pretty much stock size. Your odometer should be pretty close.

Welcome!

yotawheeler · 05-23-07, 11:55 AM

i thought i had read that the stock weight for a cruiser was closer to 4200lbs no?

for the electronic ignition do a google search on it or try looking for pentronix thats the kit i used, it ran me about $100 cdn basicly you use the same everything but you just take out the points and one or 2 other things...the kit comes with instructions and makes things clear as mud

a77fj40 · 05-23-07, 01:09 PM

I know that i should know this because it's my truck, but did the 77 fj40 have points. i have read some stuff on the internet that says that it does not have points.

thanks.

db

Tigerstripe40 · 05-23-07, 01:18 PM

Sounds like you need a carb rebuild, and to adjust the points in your distributor.

I don't agree with the "switch to electronic ignition" sentiment. If your Ignitor is good, there is no reason to switch anything out.

I run a hot 2F, Non-USA vac advance dizzy(with points!), 35" tires and an SM420. At Cruise Moab, I averaged 14-16mpgs.

I'd suggest making sure the smog equipment is in good shape and sending your carb to Jim C. or to OneSprung60 for a rebuild.

Proper timing and carbureation is key to getting good gas mileage and good performance out of a 2F.

mrmouse88 · 05-23-07, 02:11 PM

The canadian gallon isnt weird its 4.546L instead of 3.7854(stupid yanky gallons

)

As for how im getting that kind of milage, dunno, my truck is a '77 de smogged, my engine was rebuilt within the last 2 years the carb is 1 year old, electronic ignition, SOA im running 33's.

I find that my milage can take a real hit depending on where I get my gas thou. I've also found that the more i drive the truck the better the milage stays.

The other thing I find is run a can of sea foam product through the engine, both in the gas and the oil that that perks everything up.

And if memory serves me right stock wieght on a '77 should be around 3800lbs with the hard top.

cheers

a77fj40 · 05-23-07, 02:23 PM

Quote:

Originally Posted by Tigerstripe40

Sounds like you need a carb rebuild, and to adjust the points in your distributor.

I don't agree with the "switch to electronic ignition" sentiment. If your Ignitor is good, there is no reason to switch anything out.

I run a hot 2F, Non-USA vac advance dizzy(with points!), 35" tires and an SM420. At Cruise Moab, I averaged 14-16mpgs.

I'd suggest making sure the smog equipment is in good shape and sending your carb to Jim C. or to OneSprung60 for a rebuild.

Proper timing and carbureation is key to getting good gas mileage and good performance out of a 2F.

What does hot mean in terms of the engine and what is an SM420?

Please excuse my ignorance.

thanks,

db

Caddisfly · 05-23-07, 02:49 PM

I'm running 31.5" tires on my 1978 FJ. Everything else--including the 2F--is pretty much the way it came from the factory. Using a GPS, I calculated that I was averaging about 13 mpg last summer... which I thought was pretty low until I read about some FJs getting 8-10 mpg.