did it work? I'm having the same problem.
Thanks!
Thanks!
Curing Vapor Lock in a 5.7 Vortec FJ60 (1 Viewer)
- Thread starter dcoy
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- Thread starter
- #62
We don't quite have a verdict yet. My mechanic has been overwhelmed with business lately and we're having to mess with some electrical issues, a new starter, etc. before I can take it on the road. I should be getting it back in a week or so. I'll let y'all know how things go.
Just to jump in with the in-tank pump move - this will certainly make a difference in eliminating vapor lock because the pump no longer has to suck the fuel from the tank. The suction lowers the vapor point of the fuel in the line and this is why you get vapor lock.
Now, one other thing to bring up - I did a 5.3l vortec swap in my 80. I bought a Walbro in-tank fuel pump to replace the stock denso pump because the later vortecs and LSx motors require at least 60 psi to run. It worked for about a week. The pump progressively got louder and louder - to the point that it was unbearable to ride in the vehicle because of the pump noise. Yes - it as that loud.
I cured the problem by switching to a better quality pump. I bought a replacement denso pump for a 1994 toyota supra turbo. It's big, but it's whisper quiet and it has require pressure and volume ratings to meet the needs of the vortec series motors.
So moral of the story - do the in-tank conversion AND pick a high quality pump. I do not suggest walbro. For whatever reason the quality has really dropped and the pumps are really noisy.
here's the denso part number: 195130-1020
it runs about $200 and installs like a walbro, but it is larger in diameter. I had no problem installing it in place of my original pump.
Now, one other thing to bring up - I did a 5.3l vortec swap in my 80. I bought a Walbro in-tank fuel pump to replace the stock denso pump because the later vortecs and LSx motors require at least 60 psi to run. It worked for about a week. The pump progressively got louder and louder - to the point that it was unbearable to ride in the vehicle because of the pump noise. Yes - it as that loud.
I cured the problem by switching to a better quality pump. I bought a replacement denso pump for a 1994 toyota supra turbo. It's big, but it's whisper quiet and it has require pressure and volume ratings to meet the needs of the vortec series motors.
So moral of the story - do the in-tank conversion AND pick a high quality pump. I do not suggest walbro. For whatever reason the quality has really dropped and the pumps are really noisy.
here's the denso part number: 195130-1020
it runs about $200 and installs like a walbro, but it is larger in diameter. I had no problem installing it in place of my original pump.
- Thread starter
- #64
Thanks Rockrod, I'll look into that.
I put a stock Chevy replacement pump in my swap. Hasn't been tried yet though. Take a look in my thread. Sorry don't know how to link it. matt
to link got to your thread....then copy what is in the address bar (the web address)...then come back to whatever thread you are interested in...start a new msg....paste the web address you just copied into the msg.
YotaJosh
SILVER Star
dcoy - Have you had a chance to test your in tank pump yet? I'm curious how it's working out because I'm having similar issues with my TBI 350 converted FJ60. I have a TBI specific pump mounted on the frame rail right near the tank, and I'm having lots of fuel boiling and loud whining fuel pump issues.
I'm currently planning on swapping in a FJ62 tank with a GM pump installed in it.
I'm currently planning on swapping in a FJ62 tank with a GM pump installed in it.
- Thread starter
- #69
YES!!!
Finally brought it home today! A major problem was that the first Walbro pump that came in the kit from Tanks, Inc. (as insinuated above) was a dud and it took quite awhile to do diagnostics on it, contact Tanks, Inc., and get a replacement. Of course, they (Tanks, Inc., Walbro) said that the pump we sent back tested out "just fine", but we beg to differ. The pressures we were getting with it were all over the map. The new one has been spot on so far. Hopefully, we'll get some mileage out of this one. Unfortunately, the "testing" season is over with this year unless I go to the Southern Hemisphere. So far driving around town, it behaves just fine, although it is interesting that I can hear the "hum" of the pump in the cabin whereas the frame mounted pumps were nearly silent (at least with the windows closed). The pressures I see on the gauge range from 57 at idle to the low to mid 60s while accelerating. I will get some miles on it over the winter just to give it a workout with the new fuel system. Driving at speed/under load in the heat; that will have to wait till next summer. I'll let you know then.
- Thread starter
- #70
Yeee-Haaah! It works!
Finally tested my in-tank fuel pump today. The critical conditions were there (heat >100 degrees F, Elevation gain several thousand feet at speed, etc). Blasted up the grade (I-17 South from Camp Verde) at speed without a hiccup. Did three laps up and then down the mountain then back up the mountain to home. The only down side was the engine temp climbed up towards the "red" zone several times so I did turn off the A/C. Apparently, now that the fuel flows, the engine actually generates some heat. I think I'll have to go for a few more runs in the desert before the rig is cleared for use with the family but I feel pretty good about the situation after years of frustration.
Finally tested my in-tank fuel pump today. The critical conditions were there (heat >100 degrees F, Elevation gain several thousand feet at speed, etc). Blasted up the grade (I-17 South from Camp Verde) at speed without a hiccup. Did three laps up and then down the mountain then back up the mountain to home. The only down side was the engine temp climbed up towards the "red" zone several times so I did turn off the A/C. Apparently, now that the fuel flows, the engine actually generates some heat. I think I'll have to go for a few more runs in the desert before the rig is cleared for use with the family but I feel pretty good about the situation after years of frustration.
I'm down in Tucson. I put a in tank pump at the beginning. I don't have my A/C hooked up yet. I'm running Toyota radiator with home made shroud and my temps have been ok. It's the Toyota gauge though not a mechanical gauge. What's your set up? matt
- Thread starter
- #72
That's great that you did the in-tank pump off the bat, Matt. I'm still amazed that TLC (Van Nuys), the guys that did the conversion, were not keyed into the problem and its resolution. They have done many conversions with frame rail pumps supposedly without a problem.
That's a good point about the temp gauge. It is the stock Toyota gauge so it's just one step up from an "idiot light". It's sort of ironic since I have a digital fuel pressure gauge in the dash. I've been thinking about getting a Scangauge to stream the engine temp from the OBDII port. The radiator is also a Toyota radiator with the custom shroud made by TLC. I checked coolant levels and they're okay and I'm only two weeks out from an intake manifold gasket replacement. I was getting a slow leak of coolant from that location when the system was pressurized. The "spiking" of the engine temp occurred on the steepest part of the grade and the temp went back down immediately after cresting the hill. I turned the A/C off only briefly for that time. Still, it shouldn't be doing that. Down in Tucson, I assume you'd really like to get the A/C hooked up.
David
I would install an aftermarket temp gauge to make sure of what is gong on. As noted in this thread I've run an walbro external fuel pump from day one without problem in regard to vapor lock or fuel supply issue.
I do agree that an in-tank solution is best, did you post up the details on your final setup in regard to the fuel tank...type of pump, modifications required to make it work etc?
What I can share and may have noted earlier....these fuel injected engines are very temperamental in regard to fuel pressure. If you have anything that gets in the way of the correct pressure and volume you will have problems. My external fuel pump sits on the frame rail (passenger side) just a little bit foward of where the fuel lines run over from the tank to join over at the frame rail. I run a earls free flow filter between the tank and pump and then a GM OEM type filter between the pump and engine.
FYI.. I'm running A/C and I know I'm not at the same elevation but here are some recent temp readings I see on my truck....its has a 99 Vortec 5.7 and at present I use the OEM thermostat at 195F. With a/c off it normally runs around 195 and will get to 200-205 under extended load with A/C off. with a/c on it runs about 200 and will run from 205-210 under load. It always cools down at idle. I have an aftermarket 4 core brass replacement type radiator , custom fan shroud, GM OEM Fan clutch and fan.
I do agree that an in-tank solution is best, did you post up the details on your final setup in regard to the fuel tank...type of pump, modifications required to make it work etc?
What I can share and may have noted earlier....these fuel injected engines are very temperamental in regard to fuel pressure. If you have anything that gets in the way of the correct pressure and volume you will have problems. My external fuel pump sits on the frame rail (passenger side) just a little bit foward of where the fuel lines run over from the tank to join over at the frame rail. I run a earls free flow filter between the tank and pump and then a GM OEM type filter between the pump and engine.
FYI.. I'm running A/C and I know I'm not at the same elevation but here are some recent temp readings I see on my truck....its has a 99 Vortec 5.7 and at present I use the OEM thermostat at 195F. With a/c off it normally runs around 195 and will get to 200-205 under extended load with A/C off. with a/c on it runs about 200 and will run from 205-210 under load. It always cools down at idle. I have an aftermarket 4 core brass replacement type radiator , custom fan shroud, GM OEM Fan clutch and fan.
- Thread starter
- #74
Thanks Elbert.
I believe I do need an accurate temp to really know what's going on. Your numbers will be a nice basis for comparison.
I do have the in-tank Walbro mounted on the "Tanks.inc" fuel pump hanger (Post #49). I think that the driving conditions in the Southwest are somewhat unique (heat, elevation, mountain grades), and this explains why TLC has done dozens of conversions with rail-mounted/external pumps without apparent problems (although I understand they may have gone to in-tank pumps of late). Yet, soon after I initiated this thread I became aware of probably half a dozen cases in the Southwest with similar fuel supply issues that were "cured" by the in-tank pump. I think my test was pretty definitive as well, although I was moderately stressed driving up the busy, shoulderless, Interstate mountain grade, at least for the first lap or two.
- Thread starter
- #76
I thought that would be the case for the noise, but surprisingly, the fuel pump noise seems to be transmitted to the cabin more than with the rail pumps (although only really noted at idle). Not exactly a priority in the scheme of things, but I guess I'll have to finally do that Dynamat/New Carpet upgrade sometime sooner rather than later.
I did replace the fuel pump in the field a couple of times. But in this case, the need to replace was due to its position on the rail (as things have panned out).
I have tbi 5.7 and regarding the temps with a/c vs no ac in the southwest there is no comparison. I could run with no shroud, the wrong fan clutch and old stock radiator in 115 degrees heading to Payson with no overheating. After installing ac a couple weeks later all of that had to change. It would overheat idling or even pulling a moderate grade.
I added the correct clutch and a shroud and it will just handle it in the hottest weather.
The best mod for the AC however was a small pusher fan in front of the condenser to keep AC and engine temps coo at idle.
I added the correct clutch and a shroud and it will just handle it in the hottest weather.
The best mod for the AC however was a small pusher fan in front of the condenser to keep AC and engine temps coo at idle.
fan shroud mandatory with A/C, you just can't get enough directed airflow across/through the radiator without out one, plus a/c is working at idle too, where air flow is an issue when a/c is cooking.
Yeah I think a pusher fan in front of the condenser is a good option, I have the fan for mine but I've not gotten around to putting one on yet. I'm running R12 in my LC...I've not gotten around to testing the outlet temp at the vent with a/c on but it does a pretty good job. The more air across the condenser the better the a/c will cool, if no other issues in play.
Yeah I think a pusher fan in front of the condenser is a good option, I have the fan for mine but I've not gotten around to putting one on yet. I'm running R12 in my LC...I've not gotten around to testing the outlet temp at the vent with a/c on but it does a pretty good job. The more air across the condenser the better the a/c will cool, if no other issues in play.
YotaJosh
SILVER Star
I figured I'd throw in my update since I asked about the in tank pump a few posts up.
I also bought an in-tank kit from Tanks, Inc (TBI version) and installed it in my stock FJ60 tank. So far, I've had zero vapor lock issues, and I can't even hear the pump anymore when the truck is running.
I also bought an in-tank kit from Tanks, Inc (TBI version) and installed it in my stock FJ60 tank. So far, I've had zero vapor lock issues, and I can't even hear the pump anymore when the truck is running.
- Thread starter
- #80
Thanks for chiming in YotaJosh. That's good to know.
