Vehicle: '88 Jeep Cherokee
Engine: 4.0l Inline Six
Tranny: 4 Speed Auto
Oil Filter: Napa Gold 1626 (Wix)
Air Filter: Carquest Premium (Wix)
Oil Used: None
Makeup Oil: None
40%City/60%Freeway Mileage.
Period was from 9/04-1/05 in Minnesota weather.
Average Hi for period: 45 F
Average Low for Period: 28 F
Max Hi: 83 F
Max Low: -12 F
Rot 5w40= Shell Rotella T 5w40 Synthetic
Valv AC 10w30 = Valvoline All Climate 10w30
Well, wear is excellent considering the fuel loading
. The really low flashpoint and major league thinning from around 15 Cst to 11.7 (well into 30weight land)and the TBN drop are all the result of fuel loading.
Despite all that, the Rotella T Syn 5w40 seems to be holding its own in terms of wear. While Iron is high, it also fits in with the very cyclical pattern I get based on outside temps, so that doesn't worry me too much, as that trend has been going on for a while.
So, I'm still working on fuel loading.
To date: I've pulled all the plugs: all are a nice ghost white/tan color with no signs of one (or any) cylinder running rich. Plug wires and distributor all inspected and look fine. Plugs are due for replacement and will be done once its above zero (which won't be until next week).
Techron concentrate was liberally dosed throughout this interval.
CCV system checked and all lines are clear (don't think this is the cause though, as no sign of water dilution in the UOA).
Engine seems to be operating at temp (again, see no moisture buildup), and guage shows running around 190ish, even in -10 F weather.
On ocassion, I get a gassy smell when I shut it off, but it is very intermittant.
ANy thoughts on how to decrease the fuel dilution are welcome, as I don't want to start randomly throwing parts at this problem.
My current guess is a gremlin in the a sensor that causes a intermittant rich condition. Sounds like a blast to track down...
Engine: 4.0l Inline Six
Tranny: 4 Speed Auto
Oil Filter: Napa Gold 1626 (Wix)
Air Filter: Carquest Premium (Wix)
Oil Used: None
Makeup Oil: None
40%City/60%Freeway Mileage.
Period was from 9/04-1/05 in Minnesota weather.
Average Hi for period: 45 F
Average Low for Period: 28 F
Max Hi: 83 F
Max Low: -12 F
Rot 5w40= Shell Rotella T 5w40 Synthetic
Valv AC 10w30 = Valvoline All Climate 10w30
My comments:code:
Oil Rot Rot Rot Valv AC Universal
5w40 5w40 5w40 10w30 Average
Mi on Oil 4186 4192 4103 3515
Mi on Unit69182 64995 60803 52963
Date 1/05 9/04 6/04 10/03
Aluminum 3 2 2 3 4
Chromium 1 0 1 1 1
Iron 39 15 32 17 28
Copper 2 3 3 5 5
Lead 5 8 17 6 5
Tin 1 1 3 0 1
Moly 7 4 6 4 35
Nickel 0 1 1 1 1
Manganese 0 0 1 0 1
Silver 0 0 0 0 0
Titanium 0 0 0 0 0
Potassium 0 1 2 1 2
Boron 0 0 1 1 42
Silicon 10 9 11 9 12
Sodium 9 10 13 15 8
Calcium 3698 3153 2929 1939 2026
Magnesium 10 8 10 10 269
Phosphorous846 897 818 738 770
Zinc 1049 1022 984 890 935
Barium 1 2 1 0 0
TBN 1.3 2.9 2.3 1.9
Vis@100C 11.8 13.3 11.4 8.4
Flashpoint300 345 365 350
Fuel 4.5% 2.3% 1.2% 1.3%
Antifreeze0 0 0 0
Water 0 0 0 0
Insolubles0.5 0.4 0.4 0.4
Well, wear is excellent considering the fuel loading
Despite all that, the Rotella T Syn 5w40 seems to be holding its own in terms of wear. While Iron is high, it also fits in with the very cyclical pattern I get based on outside temps, so that doesn't worry me too much, as that trend has been going on for a while.
So, I'm still working on fuel loading.
To date: I've pulled all the plugs: all are a nice ghost white/tan color with no signs of one (or any) cylinder running rich. Plug wires and distributor all inspected and look fine. Plugs are due for replacement and will be done once its above zero (which won't be until next week).
Techron concentrate was liberally dosed throughout this interval.
CCV system checked and all lines are clear (don't think this is the cause though, as no sign of water dilution in the UOA).
Engine seems to be operating at temp (again, see no moisture buildup), and guage shows running around 190ish, even in -10 F weather.
On ocassion, I get a gassy smell when I shut it off, but it is very intermittant.
ANy thoughts on how to decrease the fuel dilution are welcome, as I don't want to start randomly throwing parts at this problem.
My current guess is a gremlin in the a sensor that causes a intermittant rich condition. Sounds like a blast to track down...