Diesel Forced Air Heater Fuel Supply Issue

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
About the T thing... I assumed if you install the T on the return diesel line, it's not gonna affect the engine, I was tempted to do that but lack of time and lazzyness...
Gonna tried to prime the line first to see if pump have enough pression. The whole circuit is less than 3' long. Could work. Or install a walbro pump. Keep you posted
 
One reason I use a 2.5 gallon second tank for the heater.

Many suggest to use a separate tank of fuel when diagnosing engine related problem...so the was my philosophy when I experienced heater issues and just kept it that way.
 
garrobito said:
About the T thing... I assumed if you install the T on the return diesel line,
Click to expand...

Our T comes off the 'Too engine fuel line'. I don't recall a return line to the fuel tank on our Perkins. At least I have never found one!! :eek:

Al-Ketchikan
 
AB

Sounds like the original setup was pretty good. Plus it worked! Why not use the day tank and OEM pump as intended and simplify the refill system?
 
Fuel pumps, even cheap ones, have valves that stop reverse flow. So a tee in the main supply line shouldn't allow the main to draw air. Most return lines return fuel to the tank top. Installing a tee in that line would probably cause the heater to draw air.
Today's diesel doesn't burn as well. It causes more soot. If #1 diesel is available, it burns cleaner and hotter. Also there are catalysts that cost a few cents per treated gallon that allow a cleaner burn in appliances and help engine economy.
 
With Wallas heaters, burning them hot for a few minutes before shutting them down was the trick for me...especially had it run on low for a long time.

Really didn't have to go to additives.

Pretty sure the no "tee" has less to do with air as it does with the miniscule pumps not having the guts to fight any vacuum or restriction.
 
Last edited:
"Burning them hot for a few minutes before shutting them down" smacks of running an engine hard after hours of underloading. Good practice IMO if better methods are not employed. My Wabasto always runs plenty hot as it's an on and off heater. I remember shopping for the heater and the Wallas having a "throttle" to enable it to run on low flame I considered an advantage. But maybe the Wabasto is not hot enough as my supplier advised me to use kerosene after 800hrs running dirty diesel. But the Wallace and Wabasto are very different. At night my wife would probably prefer the Wallace as it's quieter.
 
Last edited:
Nomad Willy said:
"Burning them hot for a few minutes before shutting them down" smacks of running an engine hard after hours of underloading. Good practice IMO if better methods are not employed. My Wabasto always runs plenty hot as it's an on and off heater. I remember shopping for the heater and the Wallas having a "throttle" to enable it to run on low flame I considered an advantage. But maybe the Wabasto is not hot enough as my supplier advised me to use kerosene after 800hrs running dirty diesel. But the Wallace and Wabasto are very different. At night my wife would probably prefer the Wallace as it's quieter.
Click to expand...

When I installed the Webasto Air-top 2000 on my sailboat one of the options was to have the burner burn at various intensities based on demand. This would be nice since on the sailboat the temperature range was a bit wide for comfort. However, I was advised by everyone to not do this with the Webasto as they are known to have some problems if the burner is run at full.

I never had issues on the sailboat using my diesel fuel tank as the fuel source and even after I was stupid and left it on for a long time and had it empty my fuel tank, it still fired right back up after filling the fuel tank and performing a reset of the pump and burner.
 
Wallas manufacturer tech reps said running it hot before shutdown was a good idea to burn any soot accumulation off.

Really not engine like and again, what makes sense works for me...it's a non presurized fuel furnace....soot accumulation on very low settings for long periods can bean issue, but not an indication of a "problem".
 
psneeld,
"Problem"?
Depends on one's point of view I suppose.
Does the manual mention running it hot before shutdown as a preventative maintanance proceedure? One could think of a manual trans car as having a problem because it won't shift automatically. I enjoy shifting mine and consider it a plus. Not a very good analogy .. sorry.


Dave,
My Wabasto is an Airtop 2000 also and I had no idea the burning rate was adjustable. Taking it to Sure Marine tomorrow and I'll ask about that. IMO the burn rate as it is, is close enough to perfect to call it that. However since it got crudded up running diesel it's entirely possible it's adjusted too low. But for such a small heater it does heat the boat. Not toasty well below freezing but the Willard has no insulation and I have vents that could be closed. So I'm basically very satisfied w the heater.
 
Last edited:
Anyone that thinks of a Wallas heater which is similar to a drip pot heater is anything like a transmission or engine.......well.....

...... take it up with the Wallas tech guys out in Washington State.....

For anyone with a Wallas where their thermocouple gets sooted up quickly or has hard starting or unreasonable shutdowns....try the hot burn suggestion. It usually is only necessary after days of running on low or high moisture content fuel. And Wallas tech reps agreed with the idea and proceedure. My first year was miserable, now with this knowledge, the heater has operated problem free for 3 years.

I will leave it at that.
 
Last edited:
Nomad Willy said:
Dave,
My Wabasto is an Airtop 2000 and I had no idea the burning rate was adjustable. Taking it to Sure Marine tomorrow and I'll ask about that. IMO the burn rate as it is, is close enough to perfect to call it that. However since it got crudded up running diesel it's entirely possible it's adjusted too low. But for such a small heater it does heat the boat. Not toasty well below freezing but the Willard has no insulation and I have vents that could be closed. So I'm basically very satisfied w the heater.
Click to expand...

If I recall the variability had to do with how it is controlled. Since it has been 5 years since I bothered to pay much attention to the control options, I don't recall any details.

Sure Marine are definitely the go-to guys for the heating products. They will get you setup right away. That can figure out what caused the gumming up problem. There may be some maintenance that should be done that I never did as my system always worked so darn well.

The Air Top unit is amazing as it would heat up my 40' sailboat in a hurry. The only time it struggled was when we were on the boat in 20 degree weather. It ran a lot then.
 
How about routing the engine and / or generator fuel return lines through the heater tank - with an overflow back to the normal fuels tanks - that way the fuel is clean and the tank filled up each time the engine or generator is running.
 
Searios said:
How about routing the engine and / or generator fuel return lines through the heater tank - with an overflow back to the normal fuels tanks - that way the fuel is clean and the tank filled up each time the engine or generator is running.
Click to expand...

That's generally a good idea if the engine is used often enough, but that's not the case during winter months. The thought of turning on the engine just to fill the heater tank has too many limitations -- as we use more fuel for heating than for cruising between the colder months.
 
Searios said:
How about routing the engine and / or generator fuel return lines through the heater tank - with an overflow back to the normal fuels tanks - that way the fuel is clean and the tank filled up each time the engine or generator is running.
Click to expand...

Exactly how I have my diesel stove tank plumbed. Works very well, until I don't use the main engine for more than 48 hrs, with the stove on constantly. For those times I have a small Walbro pump that pulses and can fill the 2 gal tank in about an hour.
 
psneeld said:
Al said:
Just passing on what both the manual and owners of the store said.

A lot of reading of installs and reviews...these tiny fuel pumps can be very finicky.

When my Wallas was having issues....the company replaced a pump under warranty even though it turned out not to be the problem.

That is how low their confidence in them is so I reigned my fuel supply and filters to spec just to be sure.
Click to expand...

Hi Psneeld-

Was down at the boat the other day and as a result of this thread, began to check out the Wallas system. I inspected the fuel filter, a very small unit inline installed. It appeared clear and I use #2 diesel. Still, having a spare filter other than the one I do have, in house seems a good cause so I called the Wallas dealer (By the way- who is your dealer? Asked as I was under the impression that "Sure Marine" in Seattle was the National distributor. Do you have a different source?)
Doug, the brother of the two who own Sure Marine, advised that replacement of a filter was a many years before need issue. Said the micron is 9 or very porous in terms of micron levels.
In conclusion, fuel supply of #2 diesel directly teed off the main fuel line into the DT30 carburetor. The fuel line in reality is a horizontal run with no ups or downs for the 10 foot run.
How does that stack up with your history?
Regards,
Al
Click to expand...
 
Same, they said the filter issue was pretty much a non issue. I think they said the micron size was huge...

Still they advised me not to tee into a fuel line as the tiny fuel pump shouldn't have to struggle against any suction.
 
psneeld said:
Same, they said the filter issue was pretty much a non issue. I think they said the micron size was huge...

Still they advised me not to tee into a fuel line as the tiny fuel pump shouldn't have to struggle against any suction.
Click to expand...

Good Morning psneeld, Hummmmm. First, I misquoted the micron number, it is more like a 90 micron filter. On the suction issue. Could it be that your asking your fuel to be drawn 'Up' as in a pump to draw the fuel? In my case, and never was a discussion made in the manual as I recall, or in discussion with Sure Marine (Are they your source?) regarding our specific installation. Our fuel tank,delivery, and ending to the furnace is at the same level as the engine fuel system. Actually, with full fuel tank I would suspect that there is a neutral factor between the tank and engine fuel delivery assembly.
It just seems that with a steady flow of fuel be it head pressure, or pump pressure, the flow is solid so that a drawing off by the furnace would benefit from that flow assisted then by the pump on the furnace. Everything being a positive towards the furnace without restriction.
Regardless, you have overcome the issue right? Your furnace is functioning correctly now?
Regards.
Al
 
90 micron is what I remember too.

I have no idea what the vacuum created is, just what the guys at the Walls dealership in Seattle (forget their company name)....and their recommended tee-ingredients into the vent and shoving the fuel pickup into the extra hole down into the tank versus tee-ingredients into the fuel lines to the genset or main.

Yep all issues resolved...works like a champ but annoyed I have to clean the thermocouple every year or two considering it only burns about 500 hrs a year (put an hour meter on the switch for maintenance info).
 
psneeld said:
90 micron is what I remember too.

I have to clean the thermocouple every year or two considering it only burns about 500 hrs a year (put an hour meter on the switch for maintenance info).
Click to expand...

SureMarine Is the thermocouple issue related to quality of fuel? Or-----?

Al
 
psneeld wrote;
"Yep all issues resolved...works like a champ but annoyed I have to clean the thermocouple every year or two considering it only burns about 500 hrs a year (put an hour meter on the switch for maintenance info)."

Switching to Kerosene fuel should solve the cleaning issue. Recomended for me by Sure Marine in Seattle. The dedicated fuel supply also solves all the feed supply problems too. Filling the small kerosene tank becomes a new must do also. The install is a little work so it may be easier to just keep cleaning the Wallas.
 
Yep...kerosene would probably work but I bought a diesel heater and supply it with diesel fuel on a diesel boat.

It is quicker to clean the thermocouple once every 2 yrara than run out and buy kerosene every week during the cold snaps as a live aboard.

Plus Scan Marine in Seattle did NOT recommend kerosene. They said just run it hotter more often and clean the thermocouple.

Who is Sure Marine?
 
Last edited:
Sure Marine Wish I had my card from them it is on the boat. They are two brothers who have the dealership for the Wallas line located on West Lake on Lake Union. Perhaps one of the other Wallas owners will chime in with detail. I think or recall that Wallas all they deal with and do a bang up job of customer service.
 
Any concern about forgetting to turn off pimp and overfilling the day tank?
 
Scan Marine and Sure Marine are different companies. Scan Marine are the Wallas people. May have changed their retail name to Two Mac Inc.
 
All my receipts are from Scan Marine who I believe must be the import business.

Not sure if and how Sure marine fitsvin.
 
My 'Bad' fellows, my bad.:banghead: thanks to Eric for the correction I was trusting that he would come along and strighten me out. Thank Eric:flowers:

Al
 
I installed an Espar hydronic system about 8 years ago. My plan was to T a fuel line I was using for my genset and have it shared with the Espar. I put in check valves to prevent the two from starving each other. Long story short, the Espar never ran right. It would quit for no apparent reason and the fault codes were ambiguous. Eventually fuel supply was the smoking gun and I installed a dedicated 12 gallon day tank just for the Espar, and a transfer pump to fill it downstream of the Racor. The day tank is about 6" higher than the Espar and within a few feet of it, on the other side of a bulkhead. I've had no Espar problems since even with heavy use in SE Alaska. As a post - mortem , the check valves both stuck periodically when tested , which certainty contributed to the problem. I won't use check valves in the future for anything on the boat.
 
You must log in or register to reply here.

Similar threads

P
diesel heater parts upgrades
Replies
7
Views
841
Portage_Bay
Portage_Bay
B
Flue system, high temp fuel shut up and overflow feature in Dickinson install
Replies
0
Views
251
balder8
B
P
fuel diverter
2 3
Replies
82
Views
4K
Bmarler
B
P
diesel heater ducting
2
Replies
57
Views
10K
paulga
P
M
Mainship 390 - diesel heater location
Replies
2
Views
409
Trawlerdream
T

Latest posts

Back
Top Bottom