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gas mileage
https://slantsix.org/forum/viewtopic.php?t=11594
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Author:  1speedfreak [ Sun Jan 30, 2005 7:20 am ]
Post subject:  gas mileage

I have an 83 dodge pickup 225,the lean burn has been swapped out,the carb is a bbd, timing???? don't know,I need to get timing tape on the dampener since there are no timing marks,it has an 833 od and I'm getting about 12 mpg,this seems to be on the steep side,the carb has been rebuilt and is running ok,little slugish until13 to17 hundred rpm then takes off,any suggestions,thanks,,,speedfreask.

Author:  SlantSixDan [ Sun Jan 30, 2005 9:08 am ]
Post subject: 

There is no timing tape available that will work correctly on the slant-6. It's possible the outer ring of your vibration damper has slipped, moving the timing mark away from where it should be and making it impossible to set the timing. Put the frontmost (# 1) cylinder at Top Dead Center—you can use a straightened-out coathanger or long screwdriver in the spark plug hole to watch piston movement. When your wire or screwdriver stops moving out of the hole, that's TDC. If there's really no timing mark anywhere near the timing tab, go ahead and rotate the engine until you get to TDC again and check again. If no mark at either TDC, you need to find and fix the problem that made the mark "disappear".

You don't mention what kind of service the truck is in. Is your 12mpg on the highway, putt-putting around town, a mix? Where do you live? How cold is it lately? What's your rear axle ratio? Where'd you get the distributor for your non-leanburn setup (or did someone just leave the leanburn distributor in?)

Too many variables to answer meaningfully; need more info on your setup and your driving conditions.

Author:  Doctor Dodge [ Sun Jan 30, 2005 9:23 am ]
Post subject: 

One option is to put your own mark on the dampener.
The best way to do this is to use the "positive stop" method.

The stop I have is a "gutted-out" spark plug base with a bolt screwed into it, the bolt head is rounded-off so there are no sharp edges.
I screw this into the #1 spark plug hole when the piston is way down in the cylinder.
Using a wrench on a crank bolt, slowly bring the #1 piston up until it firmly hits the "stop". Go slow, be easy so you dont nick the piston top. Mark that position in relation to zero on the timing tab.
Now rotate in the opposit direction until you hit the stop again, mark that spot. Your TDC point is in the middle of those two new marks, so carefully measure between them and punch / paint a new mark at that position.

Note: If the damper is slipping, you newly created mark will move off true TDC, if that happens, replace the dampener.
DD

Author:  Super6 [ Sun Jan 30, 2005 2:39 pm ]
Post subject: 

FWIW--the stock dampener on my '87 D150 does not have an outer ring to slip. It is a solid cast iron piece, with a cast-in power steeing pulley groove, and a timing mark every 120*. I am not sure what year this dampener started, but my best guess is they started on hydraulic slants (or just slant trucks?), '81-'87

-S/6

Author:  Guest [ Sun Jan 30, 2005 3:19 pm ]
Post subject: 

Ok, the truck is in good shape and I live in eastern pa,it's cold,it gets driven around town and highway,about 27 miles one way to work,all the swap over parts came from a76 dodge pickup 225 including the distributer,the rear gear I don't know,but its highway gears,I can get 75 mph in 3rd gear before shifting into 4th,and the dampener has a grove in it every 120%,the peace that is bolted to the block for timing is like a sigh tube not a pointer,tomorrow I'll bring number 1 cylinder up to tdc back it off the other way to tdc like the priviest post says,make my mark and see what happens.I think the motor is from a car,the starter is above the oil pan but still is hydraulic lifters,hope this helps,thanks allot,,,speedfreak.

Author:  Craig [ Sun Jan 30, 2005 6:44 pm ]
Post subject: 

Quote:
FWIW--the stock dampener on my '87 D150 does not have an outer ring to slip. It is a solid cast iron piece, with a cast-in power steeing pulley groove, and a timing mark every 120*. I am not sure what year this dampener started, but my best guess is they started on hydraulic slants (or just slant trucks?), '81-'87

-S/6
Hey S/6,
Your damper does have a rubber thingy mounting the outer ring. For what ever reason, the manual transmission slants use a solid 2 or 3 groove damper with a big retainer bolt threaded into the crankshaft. Not a single groove with sheetmetal pulley bolted on like used with an automatic transmission. Or was your truck an automatic? Did someone swap in an engine from a manual tranny vehicle? Now I"m getting confused. Seems I saw a service bulletin about that around here somewhere. Some day I'll find it.

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