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General Information => Troubleshooting => Topic started by: ORCoaster on May 24, 2011, 06:12:14 pm
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OK here's the set up. I have just replaced my rear bearings and find that the car now is in the 50 MPG range. I want to tweak the IP to go another 5 if possible. I have already removed one shim out of the cover next to the silver spring on the dynamic timing side. Question: Do I advance the pump a hair line or do I remove one fat shim and put in a skinny one? The performance is great in fourth. Hit the pedal and she wants to take right off. Not so in fifth, at 64 she just takes her sweet time to get up to say 70. Need any more information to make the call?
I am leaning towards bump the timing but that may not get the upper advance response I think I want.
So What Say Yee?
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try it and see what does the best MPGs..
just remember everything you did, so you can go back from it if you need to..
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I decided to loosen the pump and give it a line forward towards the engine. Ran about the same with fuel economy down to 47.6 from 50. going back to the old setting and see what the mileage is after that. Might pull the cover and reduce the shim on the tank after to see what becomes of the miles per gallon and the performance. Stay tuned
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are you basing your mpg readings tank by tank?
I don't think its all too accurate, as everything changes the reading. Anything above 45 is greeaatt
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Yes 8V the mpgs are only calculated on a tankfull. Wish I could get intermittent readings but all my driving is at one shot between Portland and Coos Bay. Last tank fill was yesterday. 49.6 and I didn't change anything but the amount of Wax I dissolved into my one gallon tank. I threw in 3 OZ of ATF in the gallon as well.
Going to leave it that way for a while and continue to work on getting a fitting to monitor the IP pressure.
Went all over Eugene looking for one yesterday and came up empty. Did get a tidbit on determining if Pump is good or not. While talking to the fuel injector rebuilder he mentioned that they put the pumps on a drive for about 30 seconds and measure the vacuum after about 30 seconds of cranking. If it is 18 lbs then they figure it is good.
They don't measure the internal pressure.
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So today I was able to purchase two 12 mm by 1.5 pitch thread and two nuts that go with them. My goal was to drill out the center of the bolt and solder a nut to the top. I then was going to drill out the side of the bolt and use a single port banjo to take off the pressure reading.
Basically mimicking an in-bolt setpup with a nut on top that the out bolt would sit on. It took a while to drill it all out but I got it to work. Not well as there was some minor weeping between the bolts and I finally removed the works. But not before I was able to measure my idle and mid-throttle pressures. It started off at just a little under 60 but eventually bumped over that at idle once the pump sort of warmed up. Way to high from what I know to be correct. 43.5 is idle pressure.
The upper pressure is suppose to be somewhere around 74 and mine was clearly beyond the 80 mark and pegging the gauge.
So I took the second pressure bolt that I have from another pump and put it on instead. Could barely get the car started and man did the white smoke roll out the back. I don't know who was making a bigger cloud roll up the street. Me or my neighbor mowing the grass with a bad oil consumption problem going on. The pressure was barely 20 and once I was able to race the engine it almost hit 40. So I tapped and checked the pressure regulator until I could at least have the car idle as I worked on it. Finally got the 43.5 I was looking for and it sounded pretty good actually. A lot less marbles on the plate sound. But still slightly smokey out the back at idle. I adjusted the power or smoke screw out and bumped the idle up. I took it for a run and I need to adjust it some more. Probably advance it a slight width of the pencil line. Before I could not understand why when I have the pump to the full retard position it still was to far advanced. With the pump at 60 lbs at idle I now know why.
Going to see if this adjustment knocks the crap out of the mileage this week. Although I already have over 120 miles on the tank so far. Blowing hoses off and having the diesel drain into the pavers isn't going to help either.
I will keep you posted
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update. mileage dropped to 40 mpg from 49-50. May have been all the fuel I poured on the ground every time I blew the outlet hose off the fittings I was using. 80 lbs of pressure at high rpms was not good. Noticed the steady pressure of the pump at 65 mph to be different in 3,4 and 5th gears. Readings of 74, 64 and 59 respectively.
Might try to reduce a shim in the pump on the dynamic side and see if I can get more advance at lower RPMs. The engine isn't fighting itself when I go 75 mph anymore. Less vibration at 65 as well. The rear view mirror doesn't have dancing headlights in it now.
Low mpg and the loss of the gas cap thanks to lackey attendant at the pump cost me another run to the autoparts store for a cap. Should charge the station for that one.
If dynamic advance can't come up at lower RPM do you think more advance at idle would be the next step. Or should that be the next step and leave the shims alone?
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This weekend I down shimmed the IP pump. I took the two thinnest shims from the two pumps I have and put them in on either side of the spring. Result? 75 MPG,
Nahh, just kidding. but I did make it back up in the 50 range on the 320 miles I put on. The car seems to pull better on those long gentle uphill grades. Before in 5th I would be pushing on the go pedal hard to the floor and still lose speed. Now it holds its own. IP pressure is a little higher in 5th gear and 4th. So my guess is that the advance of the timing is happening there as well. That was my hope.
But I am not sure how removing shims would increase the pressure. To my knowledge that is controlled by the regulator in the front part of the pump or the viscosity of the fluid. Right? Not by the overall resistance on a spring length.
I mixed the gallon of diesel a little different on the next batch. Two ounces of wax and 4 oz of ATF in the 10 gallon tank. That rode better still so I am optimistic that the mpgs will get a little better yet. I don't baby this thing on the highway either. Moving at 65-70 to minimize drive time.
Be a week but I should have numbers then.
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Good job, it's nice reading about other peoples experiments.
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Yes, there are few replies.. but a good read nonetheless :D
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This "spearmint" is sorta kinda coupled to the water injection task but I didn't want to mix threads. I was out thinking on that one some more and decided to pull the water bottle for now. I have to be sure I have water vapor only and not any water going into the intake. I need to develop a two stage water bubblier and capture of overflow or slosh before I feel good about the stop go traffic getting out of Portland.
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Just a bump for progress sake. Been running the water for a month and I must say it does make a difference. Not so much in mileage like I initially thought but rather in smooth revs. I used to have quite the hammer noise coming out from the engine at idle and on the mid acceleration range. Duh? it's a diesel, no not that, I know diesel noise from hard knocks that shouldn't be there normally.
I think the vapor is keeping that explosion from happening with the fuel, a slower burn?
I also am seeing the oil build up in the water tank that the engine used to burn. Not real wild about that. But it might have just been one of those things where if you don't see it well then it isn't a problem. I don't think it is a problem really, other than now I need to soak it out of there as it will never be burned now.
Some wondered about back pressuring the system and blowing oil out the dip stick. I took action on that by squeezing the rubber insert to be fatter and have had no problem. I did need to replace the hose that comes from the vacuum pump to the lower part of the engine as it went to leaking. I say old age not from the conversion.
I am now thinking how I might make a finer mist develop. Smaller and more holes in the pipe in the bottom of the water tank is the only solution I can think of. Any others out there?
Oh, water consumption is minimal. I should have marked a line on the tank for Min and Max but didn't. But there is still plenty in there and I have put about 1000 miles on it to date.
Just thought I'd pass on the progress. ;D
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Cranked the max fuel screw in by about an eighth of a turn. Gets more fuel sooner so I am not slowly creeping up to 65 now. It really goes. And the mileage. 312 miles and 6 gallons of gas that is 52 mpg. Hope it stays around for more tanks. Or gets better. Going to try and make a better bubbler. Same kind of tube across the bottom but with lots of real fine holes not the big ones I put in on one row. More small is better for froth.
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Great job.
For WI,I use windscreen res with pump-manuel switch,and I took~2L of water on 300km easy-switch~2sek only in high rpm for 2 years.I like idea of bubbler=WI,but can you get temp to vaporise water+oil(more temp)and I think that`s reason for your min on 1600km,REAL WI can use 10L/100km.
I get small steel res for heating 10bar,with tire and 3/4" conections,so I plan to use air with 2 check valves and tiny jet(what`s yours) for mist which I don`t have good now.
I`ll supply air by gas station and small tire comp.
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mtrans, I do not get as much vapor as I would like. And the oil has to be cleaned out of the tank or it seals the water off somewhat. I would have to find a metal tank to be able to heat the water up. The tank I have now is thin plastic. I would just route the coolant from the top of the radiator through some flexible copper pipe in the bubbler tank if I wanted to do that. At this time I do get some vapor moving through the lines. I wasn't really sure how much water to use. I did not want big drops in there that is what I did know.
Still working with it.
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Cranked the max fuel screw in by about an eighth of a turn. Gets more fuel sooner so I am not slowly creeping up to 65 now. It really goes. And the mileage. 312 miles and 6 gallons of gas that is 52 mpg. Hope it stays around for more tanks. Or gets better. Going to try and make a better bubbler. Same kind of tube across the bottom but with lots of real fine holes not the big ones I put in on one row. More small is better for froth.
i think you should just mount a nice bong in there and call it good.. those things already have diffusers in them, and all sorts of other bubbling devices..
HAHAHA..
j/k..
it would so work tho..
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Why yes officer some people might think that is a bong but I use it for creating bubbles that help my engine go better.
Sure son, now just step back to the car here while we have fido here sniff about a bit.
Not sure I care to be detained like that so just going to keep to fabrication of normal plumbing stock.
Did not get time to do engine work today. Spent the day doing body work. The Bentley did me wrong today. I never read where there were three 10 mm bolts going down the inside of the fender alongside the door jamb. Once I got all the others free and cut through the sealer they put on I still could budge the fender away from the door.
I couldn't see back in there very well so I jacked it up and took off the wheel and crawled into the well. I poked around on the back of the fender and found the three bolts that were keeping it from coming off. Once those were undo I just needed to pry the sealer apart. Seems like the fenders are glued on moreso than screwed on. Had a bit of rust here and there but otherwise solid. This car has sat in storage most of its 30 years. Glad I found it. Only a bit of mechanical work left to do. Working on the dents, scratches, fading paint and headliner. Carpet is so so but might have to get that out once everything else starts looking new again.
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Well, this weekend was an enlightenment moment. I had my vacuum pump go out on me and during the investigation of that bad boy I found that I have been routing a ton of oil out the pump. So I opened the top of the bubbler and there was a coating of oil across the water. Took out at least a half a cup. That may explain why the tank mileage was down to 49.4 this time. Maybe it was the 70 mph speed I was doing on the way home. Either way I hope to solve both problems with a rebuild of the vac pump and get some braking power back.
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Well, once the vacuum pump was fixed I turned off the engine and saw the water in the tank slowly rise up to the intake manifold and would have kept going but I disconnected the hose. I had just changed the oil and filter and didn't need that problem.
I plugged in a small check valve in the line so when the engine is running the air can flow to the water bubbler but when the vacuum is pulling through the engine on shutdown the valve lets some air in. I didn't have a spare check valve that could fit in the larger diameter brake booster line. Time to throw a new one on there I guess.
So be aware those of you thinking about this system that the pressure generated by the blow by is only half the potential problem. Sucking the water into you intake is also a problem. I wonder if that much liquid going in all at once would break something in the engine. Hydro-lock or something very near to it.