Tiger loop and water

Miata

I have a Roth tank w hood installed outside since last November. Tech used 45 year orginal 3/8 line.No problems but wanted line replaced. Recently had him replace with new coated line. Boiler started sucking in air after install. All fittings were checked. Still air abd boiler would operate between 5 minutes and 20 before shutting down. Bleed air and repeat. Fittings checked again. No improvement. Tech installed tiger loop. Unit ran but still air bubles. Tech replace pump and seal looked like the source of leak. No air bubbles but bleeding showed frothing ie water in fuel. Drained a gallon off bleeder then used stick w paste in tank. No color change. Now 3 days later I looked at the clear tiger loop bowl and 1/2 of fuel is dark red as before and the top half of fuel is strawberry colored w water droplets on inside bowl surface. Any suggestion would be appreciated.

Miata

Miata

Adding picture

Jamie Hall

If the system is getting air into it — and I presume that this installation has the oil line above the liquid level in the tank at some points — there is a vacuum leak. Air doesn't just magically appear! The problem is that a leak under vacuum often will not leak under pressure, so pressure testing the line won't work, nor will it show oil staining anywhere.

Don't assume that all the flares are good. If this started after the new oil line was installed, by far the safest assumption is that one or more of the flares are, in fact, leaking — and the best way to attack that is to remake all the flares (don't just try to tighten them. That may or may not work).

Miata

Thank you, but it appears that the new pump eliminated the air, but the droplets in tiger loop bowl indicates water as well as frothy oil from bleed valve w some water on bottom of bucket but none showed in tank.

Grallert

That condensation in the TL is weird. There needs to be a vacuum somewhere to allow water vapor into the dome. My guess is it is vapor. Is the fuel line one long piece from the tank to the firomatic at the pump?

How is the fuel being suckd from the tank? There was a time that the Roth suction kits were having issues under vacuum and collapsing causing high vacuum at the pump and in some cases cracking. The tiger loop can and will cover up a lot of fuel related issues. What do the contents of the filter look like?

That's a lot of water in there.

Miata

Duplex at tank w soid copper pick up. Then one flare to top of fitting and then to tiger loop.

EdTheHeaterMan

I do not believe in coincidences for the most part. However they can happen from time to time. That said, The seal on the fuel pump miraculously fails when the new fuel line gets installed. Hmmm 🤫.

Replacing the pump with new solved the problem, right? It may be the shaft seal failed (coincidence), or maybe the gasket on the strainer cover was replaced at the time of the new fuel line and the old gasket was not completely removed, Maybe the pipe connection to the fuel pump was overtightened cracking the casting at the inlet threads, Maybe there was a defective fitting. Those last three (along with several others) would fall under installer error IMHO. All of those problems would be remediated by fixing just the problem at hand, and also by replacing the pump eliminating everything on the old pump in one fell swoop. Just sayin'

TigerStop or OSV?

As far as installing any type of OSV device on your fuel delivery system is concerned, I have thought long and hard on this topic. The OSV manufacturer wants clean oil to enter their device, so they say place the oil filter between the tank and the OSV. To that point an oil filter failure will not be protected by the OSV. Placing the filter after the OSV between the tank and the filter will protect from a filter failure leak but exposes the OSV to the possibility of contamination by tank bottom deposits. If that happens, then the OSV may fail in the open position leaving the entire fuel delivery system leaking if there is a failure.

So What is an oil user to do?

My idea is to keep the OSV away from the Tank Bottom Deposits by installing the OSV at the top opening of the duplex fitting with the draw tube about 3" to 5" from the bottom of the tank. This way crud is more likely to drop out of suspension in the fuel tank draw tube. Then run the fuel line in a downhill slope from the OSV to the inside of the building or crawlspace where it will be protected from freezing temperatures. This is important so as not to make a trap in the fuel line that can cause any water from condensation to collect outside in the freezing temperatures. As soon as the fuel line reaches the interior of the basement or home, place a fir-o-matic valve then an oil filter then a one feed line to the burner area. Since a leak happening at a point of more that 3 feet lower than the OSV may create enough vacuum to open the OSV, I would recommend a second OSV be installed at a point in the fuel line 3 feet lower than the first OSV. Up to 3 OSV in one system so you drop no more than Nine feet below the first OSV. The second OSV can be installed before or after the oil filter but I would try to put the second (or third) OSV after the filter.

Once you are inside the basement install a fir-o-matic valve then run one fuel line to the burner area where you can install a Tiger Loop. The TL will ensure low velocity flow from the tank to the burner, and also create a self priming system using the two pipe feature at the fuel pump.

The TL will also offer a small reservoir of basement temperature oil at the burner, eliminating any need for an oil preheater. The TL will hide some of the common poor flare fitting or leaking gasket problems that would otherwise cause a no heat situation, calling attention the the leak so it can be addressed, but watching the clear part of the reservoir can show this problem to an experienced tech during normal maintenance and it can be addressed then.

If they would only make an OSV where you can adjust the vacuum that opens the valve, then we would only need one, and set the OSV based on the system. But that would require a technician with some brains to actually know how to make that adjustment. In a world that has so many technicians that don't even know what an OSV looks like. LOL

Miata

Thank you for all the information. I am learning quite alot. The osv that I would like to install on the top of the tank is adjustable from 13 ft above the burner down to 3ft. My drop is about 12ft. so I should be ok. I do have question relating to opening the connection on the top of the tank to install the osv and shutoff. Will the tigerloop remove the "new" air in the line or must I wait until the burner "locks out" and then hit the restart to prime the line. Thank you