Finally got engine back together, fresh heads, old short block, the backfiring is done, it starts and runs fine, idle smooth, FI seems ok.....EGR is diables due to mechanical problems, NEVER seen it do much to anything except cause problems....so the issue is a lack of power, no bucking/stalling/backfiring like it used to, heads are new, IR temp is 240 on the head metal, near the exhaust mani's....water temps seem lo....gauges and sending units are all new....started almost immediately....
so one question is....what is the poundage rating on the injectors....I would guess at 21 lbs.....
trick is, the thing has a smooth pull to it, but a total lack of power...
any clues???
the dieing at idle was cured with the crank sensor....
thing is, compression is still at 90 lbs....but it don't smoke...so go figger, also there is almost nothing on the valve cover breathers....no serious smoke there either.....the cylinders looked pretty damn good....no ledge on top, and hash marks/color ok....
:worthy:
B-300
06-07-2009, 10:22 PM
Injectors are in the 19 to 21 lbs rating at 43 psi (3 bar, an industry standard)... Magnums run at about 49 psi (3.5 bar).
A clogged converter will cause loose of power and will rattle like it has marbles in it when cold and banged on.
mrvette
06-07-2009, 10:30 PM
INteresting, because the FP was at only 30-35 or so when running, I pinched the return line and it went to some 45 or so, but that was before the head work.....I did a timing chain, and wonder if I goofed a tooth, but there is no backfire now, it pulls smooth...new radiator....water at good temps, plenty of temp drop across the core, but heads run at 240f or so, according to the IR gun...that is....
if too lean for a lack of FP I would assume some backfire or other odd response, NO??
I know earlier 80-90's GM DPFI fairly well as a hotrodder, but this is the first DPFI on a Dodge, but I have run Dodge trucks/vans for decades....
:D
B-300
06-08-2009, 12:07 AM
You may have a weak fuel pump or the strainer in the tank which is the fuel filter also could be clogging and causing low pressure/flow.
alloro
06-08-2009, 10:01 AM
thing is, compression is still at 90 lbs....but it don't smoke...so go figger,
This is the source of your lack of power. The PSI should be 130-150 and you only have 90. The problem could be worn rings or retarded valve timing.
mrvette
06-08-2009, 11:58 AM
I played with the timing, and something funny about that dizzy the way it set in there, I would think that rascal would set in there damn near square up...but no, it want to run the best with still no pull power and at about a tooth off, as if on a Gm I had the dizzy gear on backwards....same look about it....it can only go in one of two ways of course, and so I reset the timing and it's much better, but still no real snap to it....but the backfiring is gone....
so now I do wonder about that timing chain I did some months ago ....if it was retarded, I would get all these symptoms alright....I know the compression is lo, and that's with some WD40 setting on the rings/walls to stop corrosion new heads on there, so it should have been higher....I do question that cam timing myself....
that interrupter in the dizzy sets at a cocked angle too, anyone know what it's position should be with crank at TDC?? I would assume some position squared off, like fore/aft, port/starboard, for the two edges of that crescent metal....
:worthy::)
B-300
06-08-2009, 12:44 PM
The distributor rotor should point forward with #1 at TDC.
The distributor controls the injection timing and the crank sensor controls ignition timing.... The injectors won't be "phased" correctly if the distributor is installed incorrectly but the engine will still run with less power. (Not sure how to check this)
mrvette
06-08-2009, 01:36 PM
The distributor rotor should point forward with #1 at TDC.
The distributor controls the injection timing and the crank sensor controls ignition timing.... The injectors won't be "phased" correctly if the distributor is installed incorrectly but the engine will still run with less power. (Not sure how to check this)
OK that makes sense, and do therefore when I looked at it fore/aft...12/6 is the correct orientation for that button when #1 is at TDC or #6 for that matter, but fore aft on the dizzy button output....that explains a lot, that thing was at 5 o'clock when timing marks lined up. great, so cam IS retarded, and so am I for the phreaking mistake, lovely, simply wonderful....
:mad::bawl: must have changed 500 timing chains over the years, feels like it anyway....lots easier on the stand...
:YO:
alloro
06-08-2009, 05:09 PM
that interrupter in the dizzy sets at a cocked angle too, anyone know what it's position should be with crank at TDC?? I would assume some position squared off, like fore/aft, port/starboard, for the two edges of that crescent metal....
I have absolutely no idea what you're talking about here.
mrvette
06-08-2009, 05:23 PM
I have absolutely no idea what you're talking about here.
If I pop the cap/button then sending plate off the unit, I see a crescent shape plate that spins on the shaft, it interrupts the sending unit LED light beam, I presume....since 3 wires...so I was wondering about the position of that metal piece....
or for that matter, maybe a well use the rotor button, either way, I suppose...
I still think I need tear this down again....raining out, or it would be apart again....
:bawl:
alloro
06-08-2009, 07:38 PM
When it's at TDC both the rotor and the #1 tower on the cap should be roughly at the 2:00 position when looking down from behind the engine. The plate you're referring to follows the rotor, so as long as the rotor is in the correct place, so should the plate be.
mrvette
06-08-2009, 08:16 PM
When it's at TDC both the rotor and the #1 tower on the cap should be roughly at the 2:00 position when looking down from behind the engine. The plate you're referring to follows the rotor, so as long as the rotor is in the correct place, so should the plate be.
Well, uh oh...TDC for someone, either #1 or #6 obviously, and so rotor button is at more like 230 almost 3 O'clock....damn nearly pointing to pass door....if cam was in fact retarded, it would have to be pointing to ONE oclock, no?? which says with fresh chain, the front is ok,
but if not that, only 90 lbs compression with no evident wear on cylinders...
an old Chrysler hotroder buddy of mine said may be the block is high nickel??
like some imports.....
:help::crazy:
alloro
06-08-2009, 09:49 PM
if cam was in fact retarded, it would have to be pointing to ONE o'clock, no??
Nope, not necessarily. At the bottom of the distributor hole in the block is a gear that is driven off of the cam. That gear has a shaft that goes down and drives the oil pump. The top of the gear has a slot that the bottom of the distributor shaft goes into. If that gear was removed (or was lifted then dropped during the distributor removal) and did not end up back in at the correct position, your distributor could be pointing anywhere regardless of the valve timing.
mrvette
06-08-2009, 10:04 PM
I thought that gear must be pinned to the Oil pump shaft....so you say it's just a lift out?? man I wish I had all that apart with the intake....pia....
well off comes the front again, and then to examine all this to make sure everything is kosher....
lovely....so how to reposition that gear?? without pulling the intake that is....
alloro
06-09-2009, 10:12 AM
Yes it will lift out, it is not fastened in any way. I've taken a stiff wire (like a wire coat hanger) and made a small hook to reach down in there and lift it. Once it's raised up near the opening, grab it with a magnet. When I've only need to turn it, I've been able to do so with a long screwdriver.
mrvette
06-09-2009, 12:40 PM
Well, I pulled the front off and the chain was correct, talked to my olde tyme hotrodder buddy, been a Mopar fanatic for about 50 years, and he said to compare that Cloys set to another brand, just did so....no luck the woodruff keys are same as what's in there....cam at 10 crank at 1, when Dots are on top....interesting in that the keys will line up if the crank is turned a bit....
anyway, I still have compression at 90, I will prove that again in a short while, then to advance the cam one notch, and give it another try, if compression comes up to where it's supposed to be, back does the dizzy and plugs, and then to start it with a couple bolts holding the cover in place temporary....
I can run it for 30 seconds, enough to back down the drive, and give it throttle uphill to see if it will pull.....dunno what else to do...
some locals at parts house here think it's the EGR, been blocked because of being too much mess with that pipe and one exhaust mani has a broke bolt for that EGR pipe flange there....pipe was messed up and so not used, I blocked the valve on the intake....:bawl:
B-300
06-09-2009, 01:48 PM
Stock gears are marked so at #1 TDC there is a dot on each gear that line up. The crank key towards the #1 cylinder (left bank) and the cam keyway down if I recall correctly.... (The dots are supposed to be opposit each other in a straight line, not both at the top.)
mrvette
06-09-2009, 03:48 PM
I know, that's what I did, and so this trip around this morning/afternoon, I advanced it one tooth on the cam gear....
improved it a decent amount....but still backfires alot, need to get that timing down, maybe play with that gear there tmrw....I"m tired....age 65, down and up in one day is a bit much in Florida sunlight....
time for a beer, or 6....
:worthy::IDEA::D
alloro
06-09-2009, 06:01 PM
Backfiring is a sign of either a very lean condition or that the spark is firing while the valve is still opened.
mrvette
06-09-2009, 06:04 PM
What is the poundage rating for those injectors....the ones it came with were yellow, and GM type connectors....I wonder is those supposed 21-22 lbs injector are not enough.....truck engine after all....4500 lbs filled with helium...
