#3 Bleed Line Hole Burnt Through It ????????????

[Liberator*21]

1996 Merc 250 EFI...While at the ramp today trying to put some hours on the new motor, kept hearing this noise.......sounded like a High Pressure "PSSSST"/or like a high pressure pop off when a cylinder fired :eek:. Pulled the cowl and fired it up again and saw puffs of smoke everytime I heard that "PSSSST" sound. Shut it down and looked around and found #3 bleed line burnt with a hole in it in the middle of the bend about 1 1/2" off the nipple in the block. It's definetly a burn through the line. I'm open for ideas because I'm somewhat clueless :confused::confused:, it's not from contact with anything else and there's no sign of wear on the OD of the tube.

[Dave Strong]

Any wires in that area that look like they got hot? Just a thought.:confused:

Dave:smiletest:

[Liberator*21]

Nice try Dave, I thought that too, but no wires close...............:)

[sschefer]

Think it could be a bad check valve and she sucked flame?

[Liberator*21]

Steve,
This motor has the manifold type check valve and it checked good. I'm start'n to think that the quality of the hose may have had something to do with it ?

Gary

[sschefer]

Steve,
This motor has the manifold type check valve and it checked good. I'm start'n to think that the quality of the hose may have had something to do with it ?

Gary
Gary, I recently changed out a set of check valves that checked good with a syringe but were restricted with gunk. My plan would be to change the tube but if it happens again, change the check valve.

[HStream1]

Could the line have been damaged prior to assembly and the builder just not noticed it?

There is nothing in that area except wires that could have burned the hose. And surely not an overheat or you'd have more issues than a burnt hose.

I prefer to use the yellow see through Tygon fuel grade tubing on my motors.

<TABLE style="WIDTH: 100%; VERTICAL-ALIGN: middle" cellSpacing=0 cellPadding=2><TBODY><TR><TD vAlign=center width="100%">Tygon® Fuel and Lubricant Tubing F-4040-A </TD><TD style="TEXT-ALIGN: right; VERTICAL-ALIGN: middle" id=ctl00_cph1_ptTrail_tdEmail noWrap> </TD><TD style="TEXT-ALIGN: right; VERTICAL-ALIGN: middle" id=ctl00_cph1_ptTrail_tdPrint noWrap></TD></TR></TBODY></TABLE>


<TABLE cellSpacing=10 cellPadding=0 width="100%"><TBODY><TR><TD style="VERTICAL-ALIGN: top"><TABLE width="100%"><TBODY><TR><TD class=item vAlign=top rowSpan=2>http://www.usplastic.com/catalog/images/products/tubing/57327p.jpg (http://www.usplastic.com/catalog/ImageViewer.aspx?description=Tygon%26%23174%3b+Fuel+and+Lubricant+Tubing+F-4040-A&curimage=tubing%2f57327p.jpg&image=tubing%2f57327p.jpg&catid=864&itemid=23487) </TD><TD vAlign=top align=left>Tygon® Fuel and Lubricant Tubing F-4040-A
<TABLE cellSpacing=0 cellPadding=0 width="100%"><TBODY><TR><TD style="PADDING-LEFT: 3px; PADDING-TOP: 4px">Designed for safe and efficient handling of most petroleum-based products, Tygon® Fuel and Lubricant Tubing resists embrittlement, cracking and swelling. A consistent performer lot after lot, Tygon® Fuel and Lubricant Tubing is the most requested fuel and lubricant tubing for a variety of applications -- from small engine fuel lines to coolant transfer. Specifically designed to handle most fuels and industrial lubricants, Tygon® Fuel and Lubricant Tubing resists the swelling and hardening caused by hydrocarbon-based fluids. This significantly reduces the risk of failure due to cracking and leakage. Its minimum extractability safeguards the liquid or vapor being transferred against adulteration. Extremely flexible (Shore A, 57), tubing simplifies installation, even in tight places. It is translucent yellow for positive identification and to allow easy flow monitoring. It is routinely used to handle gasoline, kerosene, heating oils, cutting compounds and glycol-based coolants. Max working temp 165°F. UV and ozone resistant. Standard length 50'. Tubing is priced per foot; sold in 10 ft. intervals only.

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[Liberator*21]

Steve,
I went to my local AutoZone parts store and pick up some heavy wall vacuum hose .125 ID x .360 OD and replaced every bleed line and TyRap'd them all (just as a test ;)). Took the boat out again today and ran it for 5 hours at various RPM's & idle, no issues what so ever. This leads me to believe my brand new (El Cheap-o) bleed lines were at fault. I'll order up some Tygon F4040A tubing per your suggestion....Do you have a source to order from ??????......Thanks :thumbsup:.

Gary

[HStream1]

Steve,
I went to my local AutoZone parts store and pick up some heavy wall vacuum hose .125 ID x .360 OD and replaced every bleed line and TyRap'd them all (just as a test ;)). Took the boat out again today and ran it for 5 hours at various RPM's & idle, no issues what so ever. This leads me to believe my brand new (El Cheap-o) bleed lines were at fault. I'll order up some Tygon F4040A tubing per your suggestion....Do you have a source to order from ??????......Thanks :thumbsup:.

Gary

Here's the Link. You're going to want the 57328. You have to buy in 10' lenghts.

http://www.usplastic.com/catalog/item.aspx?itemid=23487&catid=864

[Liberator*21]

Thanks Bud :thumbsup:, sorry for the name mix up.........:o

Gary

[HStream1]

Thanks Bud :thumbsup:, sorry for the name mix up.........:o

Gary

No problem, Steve the person is OK in my book. He can't help what he was named :D.

[Liberator*21]

No problem, Steve the person is OK in my book. He can't help what he was named :D.

LOL..................Thanks to both of you :thumbsup:

Material ordered, thanks again. Are you using anything to hold them on (i.e. Ty-Raps/mini spring clamps etc.) :confused:

Gary

[HStream1]

LOL..................Thanks to both of you :thumbsup:

Material ordered, thanks again. Are you using anything to hold them on (i.e. Ty-Raps/mini spring clamps etc.) :confused:

Gary

Nothing, just slide them on dry, there a good tight fit. Not enough pressure to cause a blow off. It's interesting to see what happens as the motor runs from idle to higher RPM's (on the hose of course).

[RB in NM]

Most hobby shops that sell remote controlled airplanes and cars / trucks, sell Tygon fuel line in various colors and sizes. They sell by the foot or roll if needed. Lawn mower repair shops will usually carry the yellow Tygon for fuel line replacement as well. I like to buy mine at the Hobby Shops,,,, they sell PINK hose,,, it's definately the fastest on the market !

Russ

[HStream1]

Most hobby shops that sell remote controlled airplanes and cars / trucks, sell Tygon fuel line in various colors and sizes. They sell by the foot or roll if needed. Lawn mower repair shops will usually carry the yellow Tygon for fuel line replacement as well. I like to buy mine at the Hobby Shops,,,, they sell PINK hose,,, it's definately the fastest on the market !

Russ

You are correct BUT

Not at .68cents a foot.

[RB in NM]

You are correct BUT

Not at .68cents a foot.

Yep,, My replacement bleed line was like 75 cents per foot. But being able to put money on the counter and walk out with the product in hand is worth 7-8 cents extra per foot IMO.

[HStream1]

Yep,, My replacement bleed line was like 75 cents per foot. But being able to put money on the counter and walk out with the product in hand is worth 7-8 cents extra per foot IMO.


If I could find it around here at .75 a foot I'd buy it over the counter. But the cheepest i've found it is 1.35 + - .10 cents.

[Liberator*21]

All I can ad is I placed the order yesterday (6/8) online, and recieved a UPS confirmation that it was shipped, after checking the UPS tracking number, it stated that it's out for delivery,which means I'll have it before 4 PM today and on the motor tonight (6/9).........now that's what I call service.

[HStream1]

All I can ad is I placed the order yesterday (6/8) online, and recieved a UPS confirmation that it was shipped, after checking the UPS tracking number, it stated that it's out for delivery,which means I'll have it before 4 PM today and on the motor tonight (6/9).........now that what I call service.

I have received the exact same service from them when I ordered.

[RB in NM]

You can not beat that turn around time fer sure, Quick.

Russ

[Liberator*21]

Think it could be a bad check valve and she sucked flame?


Ok, somebody explain this one to me "SUCKED A FLAME", I don't quite understand what it means other than the obvious, but how and why ????????????

P.S. New bleed lines are on..... :thumbsup:

[modvp]

I am also thinking about replacing the tubing on my 1999 250 efi. How many feet did you use...was 10 feet of tubing enough to complete your 250 efi?



Ok, somebody explain this one to me "SUCKED A FLAME", I don't quite understand what it means other than the obvious, but how and why ????????????

P.S. New bleed lines are on..... :thumbsup:

[Liberator*21]

To be honest with you I don't know. I just ordered 20' to cover my a$$ cause I know with my luck I'd come up short...............LOL

[modvp]

Thanks, I'll do the same.

[Liberator*21]

I know allot of folks don't secure the bleed lines to the nipples, but I do. If you happen to do the same, use only brand name Ty-Raps having a stainless steel locking tab. The El-Cheap-o plastic ones will soften with heat and loosen up on there own. Good luck.

[sschefer]

Ok, somebody explain this one to me "SUCKED A FLAME", I don't quite understand what it means other than the obvious, but how and why ????????????

P.S. New bleed lines are on..... :thumbsup:


I was just thinkin what might cause a burn through.. If the bleeder was wide open then pressure would go both ways. You definitely don't want it comming back into the intake and if there was preignition or detonation occuring there's a slight possibility the the flame could have been sucked in. The piston is on the upstroke when detonation and pre-ignition occur.

However, now that you seem to have resolved the problem, I bet it was sitting on the bench and someone knocked a soldering iron into it and never noticed it.

[Liberator*21]

Steve,
I can assure you that those lines were all new and undamaged. Maybe just a stroke of bad luck that one time. On my motor I have "ONE" single manifold per side (see pic below), I don't have individual check valves as the 98' models started with. As you can see my bleed ports are between the cylinders not in the middle of the cylinders as the newer models were. There have been many changes over the years on the bleed routing and it's confusing as hell as to why there all so different from one another.
http://i45.tinypic.com/2cs9i76.jpg

[sschefer]

Yeah, I see what you mean. I was lookin at my 2.0 and trying to figure how the heck it happened. I couldn't come up with anything eles that would cause enough heat to burn through like the picture I had in my head.

[opsdave]

I am also thinking about replacing the tubing on my 1999 250 efi. How many feet did you use...was 10 feet of tubing enough to complete your 250 efi?
When I replaced the bleed lines on my 2000 225 EFI I ordered 20' and it was not enough. I dumped the VST and mounted a Mallory EFI fuel pressure regulator on the side of my MAD EFI intake where the VST used to live. If I wouldn't have run the vacuum line to the regulator 20' would have been JUST enough. I ran the same thin walled stuff that Gary had trouble with on his and burnt a few when I had #2 and #3 injectors crossed. I ordered 30' of the Tygon tubing to be safe this time. It just got delivered to my house and will be installed this weekend.