Author Topic: Finally had a chance...  (Read 4849 times)

Offline dvdswan

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Finally had a chance...
« on: December 29, 2013, 10:20:05 pm »
So I finally had the chance to actually give the truck a test drive and find any more quirks in it.  remembering that the truck is 35 yo, I thought of all issues that would be needing quick attention, put on the back burner or just remember when I have some time.

Clutch:  seems soft or light but does grab where it is suppose too.  I'm probably used to my Nissan clutch.

Transmission: SM465, shifts solid, didn't try to shift without the clutch, probably should have, but down shifting into first I had to come to almost a complete stop, like under 5 mph.  didn't bother with low.

spedo:  I'm wondering if my speedo is registering faster than it should, when I was at 40 mph and in third gear the rpms seemed really low, I don't have a tach to compare though.

fuel gauge:  the needle will sometimes float like gas is sloshing in the tank, do the tanks have baffles in them?

ignition:  when I would shut the truck off it would take a second or two for it to shut down (like a delay, it did this only two or three times of the 7 or 8 times shutting off the truck), like the switch is worn or going bad.  almost like my old tilt column would act up if the tilt wasn't in the center position and it was loose.  this column is tight and not wobbly so its a guess that its the switch.

brakes:  firm pedal but brakes seem soft, I plan on inspecting them next weekend, wondering if I have an axle seal leaking

oil pressure gauge:  not sure if its elec. or mech. ( I haven't dug that far into the truck yet) but it was steady for the most part.  it did bounce a couple of times at idle but smoothed out. 


I know this is long but I appreciate any thoughts on these items...

Offline Stewart G Griffin

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Re: Finally had a chance...
« Reply #1 on: January 01, 2014, 10:19:35 am »
Do you live near an interstate or major highway with mile markers?

The only thing i can suggest for now is to have a stopwatch and try to time how long it takes to cover a mile at 60mph.  If 60 seconds, then the speedo is pretty much on.  There are charts to determine what the actual speed is if it's more or less than 60 seconds.   Remember tire diameter could affect speedo calibration.

Offline bake74

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Re: Finally had a chance...
« Reply #2 on: January 01, 2014, 10:33:27 am »
Transmission: SM465, shifts solid, didn't try to shift without the clutch, probably should have, but down shifting into first I had to come to almost a complete stop, like under 5 mph.  didn't bother with low.

     Yes, with a SM465 you almost have to be stopped to get it into granny low.

spedo:  I'm wondering if my speedo is registering faster than it should, when I was at 40 mph and in third gear the rpms seemed really low, I don't have a tach to compare though.

     I have a chase car with me to determine the speed difference at different speeds of the truck. (I usually do 30, 50, 60, and 70, as Stewart G Griffin mentioned that will work for 60 mile an hour. )    As far as clocking if a mile is a mile, you can use GPS if available and you can do that at different speeds, if your GPS is capable of clocking mileage.

fuel gauge:  the needle will sometimes float like gas is sloshing in the tank, do the tanks have baffles in them?

     No baffles in the tanks that I know of, but I could be wrong about the later years.

ignition:  when I would shut the truck off it would take a second or two for it to shut down (like a delay, it did this only two or three times of the 7 or 8 times shutting off the truck), like the switch is worn or going bad.  almost like my old tilt column would act up if the tilt wasn't in the center position and it was loose.  this column is tight and not wobbly so its a guess that its the switch.

     That should be your main concern to figure out what caused this, if it is your column or timing or ?
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom

Offline dvdswan

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Re: Finally had a chance...
« Reply #3 on: January 01, 2014, 09:28:44 pm »
well, I drove it some more yesterday and today.  the speedo is off by 10 mph, at least is stops at 10 mph and when I'm on the freeway 70 is 60, I had a Prius next to me and I saw the speedo.  the odometer is pretty much dead on.  can I put the speedo needle off and push it back on at zero?  tires are 31s, originals are 78x278PPs or something like that.   so the speedo would go slower not faster.  the seller told me it had 4.11s in the truck, but there is no sign on the build sheet in the glove box for 4.11s so I'm guessing it came with 3.73s.  I need to jack up the rear and spin and count the tire/d-line rotations.  need to check the gov lock as well.

the trans, after it warmed up  it dropped into 1st (not low) at 10 to 15 mphs with no issues.

ignition did it again today at Lowe's, I'm guessing the ign. sw. under the dash is going bad, loose, or really misadjusted.  it doesn't diesel, but idles normal.

Offline Captkaos

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Re: Finally had a chance...
« Reply #4 on: January 02, 2014, 08:46:58 pm »
can I put the speedo needle off and push it back on at zero?
This won't do anything but potentially break the needle, it is indexed on.  If you speedo it off it needs gears swapped to correct it.

1987 EFI tanks are the only ones with baffles..  It has very little effect on fuel rise sine it isn't that tall...

SM465:  1st or Granny, there is now way you will downshift to Granny, and generally you want to be going fairly slow to downshift to 1st.

Clutch:  do you mean soft as in pedal feel?


Offline Stewart G Griffin

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Re: Finally had a chance...
« Reply #5 on: January 03, 2014, 01:20:29 am »
Totally forgot about GPS.  This would work great to verify speedometer/odometer.

Offline dvdswan

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Re: Finally had a chance...
« Reply #6 on: January 03, 2014, 11:03:52 am »
can I put the speedo needle off and push it back on at zero?
This won't do anything but potentially break the needle, it is indexed on.  If you speedo it off it needs gears swapped to correct it.

1987 EFI tanks are the only ones with baffles..  It has very little effect on fuel rise sine it isn't that tall...

SM465:  1st or Granny, there is now way you will downshift to Granny, and generally you want to be going fairly slow to downshift to 1st.

Clutch:  do you mean soft as in pedal feel?

so the speedo I will live with until I do for the rebuild, I'll just test the speedo with my garmin and remember it from there.  its seems to be 10 off +/- 1

so look for a 87 plus tank then?  again this would be part of the rebuild.

I always looked at the trans as a L-1-2-3.  I know you can't go into low unless the vehicle is stopped.  so 1st is good then around 10 mph.

as far as the clutch.  i think it grabs just fine (around 1/2 pedal) and I have the 3/4"-1" free play the top, soft or light in grabbing power, I'm guessing I'm just not used to a manual clutch.  it has decent spring pressure, no rattle from the t/out bearing.  I'll drive it some more, its probably just me. 

again, thanks for the replies.  I know I've got tons of questions but all of those are more for the rebuild when I start that.

oh, one more thing...  my bed floor boards need replacing, can I use 1x6 from the lumber yard or do I need something special?  these will be more of a temporary thing but the 2 outer boards are the bad ones and the rest seem to be decent and will definitely last for another year I would think.


Offline bake74

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Re: Finally had a chance...
« Reply #7 on: January 03, 2014, 08:53:45 pm »
     If you are going to be replacing your bed boards anyway, use what you got, or put a piece of plywood in it.
#1: The easiest and most obvious solution to any problem is 99% of the time correct.
#2: There is no such thing as impossible, it just takes longer.
  74 k10, 77k10    Tom