• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

TR4/4A Sputtering when hot TR3 & TR4

Share this page

Don Elliott

Don Elliott

Obi Wan
Offline
I just got back from VTR (1800 miles total) and whenever I got stuck in traffic and the temperature gauge started to hit 185 and higher, I flicked on my 12" Kenlowe 10 blade shrouded pusher fan on my TR3A. Several times when the traffic stopped for 5 minutes or more where 2 lanes narrowed down to 1 because of construction and once (2 hours) when a semi-trailer rolled and blocked both lanes, the temperature stayed at 185, but I'm sure the engine compartment got hotter than normal. When I'd get going again, the engine would stutter or sound like it was running on only 2 cylinders during normal or hard acceleration. Feathering the gas pedal helped a bit and after about 2 minutes, it was all cleared up and running as it should.

A friend with a TR4 told me he has the same problem.

I suspect that the addition of 10% ethanol is creating vapour lock and after 2 minutes driving, the cooler gas is now getting fed to the float bowls and the problem disappears. I have never had this problem in Canada where we don't have ethanol in our gas. And I never had the problem before with US gas during trips to USA.

Any comments ?

Don Elliott, 1958 TR3A.
 
Don - altho' I haven't had the opportunity (yet) to drive a long distance using the latest E-85 ethanol enriched fuel, I have read several articles on the tendency of older engines to have the trouble you described. Here's one:

https://www.startribune.com/432/story/59974.html

Another article (by the National Corn Growers Association - by strange coincidence) mentions that few modern cars experience vapour lock using E85 fuel, as "all major auto manufacturers now use in-tank fuel pumps, which are not subject to vapor lock problems as were the older in-line fuel pumps".

https://www.ncga.com/ethanol/main/your_car.htm

Interesting to hear if other Canadian TR drivers have experienced this problem while in the USA.

Tom
 
I have not experienced that problem with the ethanol. Did you purchase the premium or the regular grade gas? I have problems when I use the low and mid grade gasolines but only that it runs poorly (irregular rpm). No problem with the premium grade gasolines over 90 octane.


I would think just heat related vapor lock or perhaps a lazy or sticky float and or needle with all the stop and go traffic?

You may want to inspect your rubber seals and float needles but I don't think you were exposed long enough. Usually the ethanol/gas has to sit there for a couple of weeks before it eats away at or turns your float needle valve tips (If they are rubber) and rubber o-ring seals to a sticky jelly blob.

BTW - I know you've driven farther but 1800 miles is a loooong ride in a TR3. Congratulations!

/bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif
 
It happened three or four times on the way down on 2 different tanks of Mobil 92 octane - and once on the way back. I don't remember if I saw any warning about added ethanol. The sputtering didn't happen when I filled twice in Downingtown PA at a Wawa gas station with 92 octane that had no signs warning that "this gas may contain ethanol".
 
Don, have you thought about Joe Alexander's heat shield?
 
Yes I had, but my TR3A is not only my reliable long distance touring car but it's also a concours car. I don't want to put on a non-original item until I've narrowed down all possible solutions. I may just have to live with it. Or stay out the USA. Or find gas stations which don't have ethanol.

I finished the assembly of the car on the Tuesday before VTR and tested the new engine around home for 90 miles mainly to set the timing, richness, etc. So I left fot VTR with this virtually new engine, - new bearing shells for the crank and con-rods, new rings, honed bores and one valve and seat that had to be ground. I drove 780 miles by the time I got there.

In the concours with 8 entries in my early TR3A class, I took 2nd with 387 points out of 400. First was towed there and had 392 points. I now have over 1900 miles on the car and the new engine. The sputtering had me a bit worried as you can imagine when it surprised me suddenly.

https://www.triumphest2006.com/images/clubcars/30donelliott'str3.jpg
This photo is from VTR 2001 in Colorado.

Don Elliott, Original Owner
 
Sounds exactly like "hot fuel" problems to me.

I believe current US law requires at least 10% ethanol in all gasoline sold for automotive use (plus has specific guidelines for volatility and other parameters); so your only hope of getting non-alcoholic gas here is to buy either aviation fuel or farm fuel (both of which are illegal to use on the road).

And since you don't want to modify the car, I don't know of any other solution beyond living with the problem.

Sorry.

IMO there is some small hope the problem can be solved in the future, but our current government would be just as happy to completely outlaw driving anything without computer controlled fuel injection, so I don't see any solution soon.
 
Is the 10% formulation sold year-round in some areas? My recollection (vague) is that we only get that in the gas in the winter months in AZ.

At any rate I have never experienced a problem with it. The only heat-related problem such as you describe was due to a failing coil. Finally worked that out when it failed completely (real easy to diagnose then).
 
I've run the 10% mix here year 'round for about 10 years or so, and have never experienced any problems, even when the ambient temp was hovering around 100F.
Jeff
 
Randall - I'll live with it or just stay out the USA.

Don Kelly - I suspected that something was wrong (malade in French means sick) with the re-built engine but it ran fine 99.5% of the time, so I eliminated that as a source of the problem. It's ticking over better than new.
 
Geo Hahn said:
Is the 10% formulation sold year-round in some areas?
Click to expand...
It certainly is here.
Geo Hahn said:
My recollection (vague) is that we only get that in the gas in the winter months in AZ.
Click to expand...
The Clean Air Act was amended in 2005, so the change is relatively recent. Used to be that 'reformulated' gasoline was only required in areas with smog/ozone problems; but as I understand it the amendment basically made using ethanol a requirement in all areas.

In any case, I'm not convinced that the ethanol itself is the problem. The overall physical properties are controlled for the area and time of year the gasoline is sold in, to attempt to achieve the best balance between things like absence of vapor lock and complete combustion. So the stuff you buy in AZ is likely a lot different than what Don got in NY or PA.
 
Aloha Don,

Check to see that the vents on each of the float bowl covers are open. I had a similar problem on my MG and one of the vent was plugged. It would create a vapor lock problem during low fuel flow period like idling at a traffic stop, slow moving traffic, etc. It also made starting the car very difficult unless sufficient time passed for the engine to cool down. The car would essentially be running on only carb.

You should have received points for driving you car to the event. After all it is a car, not a full scale model.
 
Don Elliott said:
...filled twice in Downingtown PA at a Wawa gas station with 92 octane that had no signs warning that "this gas may contain ethanol".
Click to expand...

As a local to the philly area and a regular patron of WaWa, I'm certain the WaWa gas in downingtown contains ethanol.

I didn't read anyone suggesting that the trouble might have been mixture. I would suspect that the idle mixture might have to be adjusted a tad to compensate for canadian vs, us fuel, for changes in climate, as a motor is broken in.....

Maybe I'm stating the obvious and you made frequent adjustments on your long trip....
 
In over 1800 miles, the only adjustment I made was to lower the idle setting screws. I haven't touched the mixture since I left. Yesterday, I fill up with Canadian Shell, drove 175 miles and no problems. I must add that there were no traffic conditions to overheat the engine compartment and the ambient was about 70 deg. F.
 
I once saw a pic of a restored TR3 in a Classic car mag that had "louvres" in the bonnet. It looked great and I'm thinking it would greatly reduce underhood temperatures.
 
Don cutting a hole in his 3, That will never happen!
 
Re: Sputtering when hot TR3 & TR4

Here to revive an old thread, despite all my efforts in shielding heat (manifold heat shield, insulating-wrapped manifold, fuel lines with fire shield) my TR4 is experiencing severe vapour lock in extreme conditions: 90+ degrees ambient, push it a bit, park it, get back to it and it drives like it's running on 2-3 cylinders under load. Let it sit and it all goes away.

Completely forgetting about the possible effects of ethanol, I'd been putting Petro-Canada 94 (10% ethanol) exclusively this year intentionally feeding it "the best".

I'm almost on empty and will be filling it up with Shell or Ultramar 91 which don't contain any ethanol and I will check back here with the results!
 
Re: Sputtering when hot TR3 & TR4

Give the following website a look: https://pure-gas.org It lists stations in the US and Canada that sell ethanol free gas. In central Alabama, many stations around large lakes and the rivers most commonly used by fishermen sell ethanol free gas to boaters (stations not located at marinas). Within 10 miles of me, the direction I hardly ever travel in, a logging company owns a gas station that sells only ethanol free gas.
It's there, just sometimes hard to find.
 
Back
Top