unleaded fuel in older engines

   #1  

Anonymous Poster

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Sep 27, 2005
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Howdy,
Although I have run unleaded gas in older "leaded" engines,what would be the down side of doing this?I ask because I note that some of you own and operate some older tractors that must have been running on unleaded for a good many years,as it has not been available to purchase for quite some time.......
Thanks in advance.....
 
   #2  

JJT

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Oct 13, 2001
Messages
1,215
Location
Upstate NY, USA
Tractor
Kubota L3710 HST and a Kubota ZD21 60Pro
Play it safe and add a fuel conditioner. Unleaded gas in an engine that was built for leaded gas is not a good thing. The valve train in the old engines requires the cushion/lubrication that lead provided. The valve seats in many of the old engines were not as hard as they are in more modern equipment.
 
   #3  

pfoxy

Silver Member
Joined
Apr 26, 2001
Messages
105
Location
Maine
Tractor
1988 John Deere 750, 1938 McCormick-Deering (Farmall) F14
Lots of folks subscribe to JJT's view, and that's certainly a very reasonable thing to do. Fuel conditioner is not that expensive, nor is it a hassle to deal with.

My view is that unless you're REALLY working that engine (plowing or heavy tillage) you're never gonna get it hot enough for unleaded fuel to cause a problem, so I just don't worry about it. My old F14 probably doesn't get a hundred hours a year put on it.
 
   #4  

MJB

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Jun 1, 2000
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499
Location
Syracuse, New York
Tractor
1952 Case DC-4, 2001 JD4300 MFWD, HST
I put a quart of 2-cycle water-cooled engine oil in with 20 gallons of gas in my old 1952 Case DC. This will give about an 80:1 ratio. So far, in the 10 years I have owned the tractor, I have not had any sign of sticking valves or other engine problems. When I first bought the tractor, it had sit unused for quite some time and had low compression on 2 cylinders. I found a broken valve spring on one valve, a couple of valves that were corroded enough on the stem to keep them from closing fully, and most of the valve seats were pitted. I had the head re-built, and it has run like a champ ever since. I think the 2-cycle oil should provide enough upper cylinder lubrication to keep the problem from cropping up again. Also, I like the idea that the 2-cycle oil will coat the surfaces of the upper cylinders and valves enough to hopefully prevent any rusting when the tractor sits unused for a while, which happens much more often since I got my JD 4300. I have heard of others that substitute automatic transmission fluid or diesel fuel for the 2-cycle oil. Hope this helps.
 
   #5  

Soundguy

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Mar 11, 2002
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Central florida
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RK 55HC,ym1700, NH7610S, Ford 8N, 2N, NAA, 660, 850 x2, 541, 950, 941D, 951, 2000, 3000, 4000, 4600, 5000, 740, IH 'C' 'H', CUB, John Deere 'B', allis 'G', case VAC
Anyone use the 'lead substitute' that most auto stores carry?

I'm guessing all the ford 2/8/9n owners are dealing with this situation, etc.

Soundguy
 
   #6  

RichZ

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Apr 4, 2001
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Location
White Creek, New York, Washington County, on the V
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Kubota 4630 with cab and loader
When I bought my first vintage tractor last year I pondered the same question. I read several antique tractor restoration books, asked the question on several forums on Yesterdaystractors.com, and asked several independent tractor mechanics in my area, who maintain mostly vintage tractors. I got the same answer every single place. Unleaded fuel won't hurt anything. I've used unleaded in both my Ferguson and Oliver with no conditioners and never had any problems. One of my best friends in my area is a farmer who works with a fleet of old Minnie Molines and old Fords. He uses straight unleaded also./w3tcompact/icons/smile.gif
 
  
  • Thread Starter
#7  
OP
A

Anonymous Poster

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Joined
Sep 27, 2005
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0
Howdy,
Thanks for the response.Have been leaning towards getting an "older" tractor and was leaning mostly toward diesel due to the "unleaded issue"...
I beleive that the classics have style,and I want to admire it when I'm not using it......
 
   #8  

Youare

Platinum Member
Joined
Aug 9, 2001
Messages
990
Location
Winchester, New Hampshire
Tractor
Kubota L3000
I have an 8N that has been around the place for better than 20 years. Leaded fuel has not been sold here for many years and I worried about the damage I assumed would happen with unleaded fuel.

For a while I added the lead substitute, but some times I ran out for a while. Then it seemed a better solution was to add a little marvel mystry oil to each tank or gas, ran out of this often too.

Well, every 20 gallons of gas or so gets a dose of marvel oil and I don't see any side effects with stuck valves yet.

Randy
 
   #9  

RobertN

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Apr 6, 2000
Messages
8,532
Location
Shingle Springs California
Tractor
New Holland TC40D
A point to ponder/w3tcompact/icons/grin.gif Most older gas engines in tractors operate at lower rpm's than cars do. Most also have lower compression.

My 41 Farmall A revs out at about 1500 rpm. Look at how high car engines rev compared to that. Heck, on a lot of engines, that's near the fast idle rpm.

I imagine the lack of lead does not help the older engines. But, I do not believe it is nearly as critical as in a higher revving, higher compression engine.
 
 
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