Compression Test today
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Freshman User
Joined: Jan 2010
Posts: 32
Likes: 0
Compression Test today
I've been debating a rebuilding and swapping a motor in since mine has 180k on it. I found some nasty cream colored guck under the oil filler cap as well. That got me worried a bit so that promted compression test.
I did a dry test and got:
135
152
140
145
145
135
Seems alright though 1 and 6 are just over the 10%. I donno why #2 was so high. Anyway, what do you think? Do I need to start a rebuild now or does it look ok for a while? The truck is running pretty dang well right now.
I did a dry test and got:
135
152
140
145
145
135
Seems alright though 1 and 6 are just over the 10%. I donno why #2 was so high. Anyway, what do you think? Do I need to start a rebuild now or does it look ok for a while? The truck is running pretty dang well right now.
Elder User
Joined: Aug 2007
Posts: 537
Likes: 0
From: LaGrande,Ore
Rebuild?
Without more and detailed information, a difinitive answer to your querry can not be forthcoming. Oh Boy, If that aint a load. Sounds to me like your vehicle gets a lot of short trip/ not fully warmed up use. The numbers look OK. I think your high #s may be carbon build up, and the lows due to cold cylinders (1,6). What do the spark plugs look like? How often do you get to run your vehicle at temperature for an extended time (1 hr + ), and how often do you service it? The cold cylinders wear more than properly warmed ones. If you have no other problems than what you have listed? , then 180 k is just broken in well. Another problem with short trips/ cold engine driving is the formation of sulfuric acid in the engine oil. Over time this will eat the bearings right out, as they are the softest metal in the engine. I'm a font of information, not all correct or good. Ask others, then you decide. Best of luck OBCB
Thread Starter
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Freshman User
Joined: Jan 2010
Posts: 32
Likes: 0
Thanks for the info!
I've only had the truck a couple months with no real issues. Most of the driving I do is 8 miles each way to school and back (I teach chem!). I did notice the truck not warming up well in that time so I just put in a 195 thermostat. I've done the following since I got the truck:
- Plugs (today) ... old plugs looked ok but REALLYdirty around the threads. They were bosch's I replaced with copper autolites.
- Plug wires
- oil and filter change
- air filter
- 195 thermostat
I've driven it long a couple times, but pretty much about 16-20 miles a day is about it. Some days it sits. As for mechanical areas that I was concerned about:
- gunk underneath the oil cap
- dip stick is not pristine
- LOTs of oil around the oil pan and underneath (though it doesn't seem to leak or use much...about 1/2 qt in 1000 miles)
- exhaust smell in cabin when I'm stopped (I think I can hear a leak)
What I really want to know is should I worry about using the little cash I have trying to find/rebuild a motor because this one is on the way out OR can I use the cash elsewhere on the truck?
I'm happy to give as much info as you guys need. THoughts?
I've only had the truck a couple months with no real issues. Most of the driving I do is 8 miles each way to school and back (I teach chem!). I did notice the truck not warming up well in that time so I just put in a 195 thermostat. I've done the following since I got the truck:
- Plugs (today) ... old plugs looked ok but REALLYdirty around the threads. They were bosch's I replaced with copper autolites.
- Plug wires
- oil and filter change
- air filter
- 195 thermostat
I've driven it long a couple times, but pretty much about 16-20 miles a day is about it. Some days it sits. As for mechanical areas that I was concerned about:
- gunk underneath the oil cap
- dip stick is not pristine
- LOTs of oil around the oil pan and underneath (though it doesn't seem to leak or use much...about 1/2 qt in 1000 miles)
- exhaust smell in cabin when I'm stopped (I think I can hear a leak)
What I really want to know is should I worry about using the little cash I have trying to find/rebuild a motor because this one is on the way out OR can I use the cash elsewhere on the truck?
I'm happy to give as much info as you guys need. THoughts?
Elder User
Joined: Aug 2007
Posts: 537
Likes: 0
From: LaGrande,Ore
Spend the money!!!
None of us Ford owners ever spend any money. We don't need to, our vehicles last forever with no maintainence. HAHAHAHA. Two things; You can never know what might be hidden/ masked by other symptoms, so you need to correct items as you find them. (ask advice,weigh responces, make your decission,etc). Any safety issues #1!, reliability #2, all others after that. You seem to have started out in the right direction with your repairs. I'm not much for addatives, but this one works well for me " RISLONE " a Schaler product. I use 2 quarts with 4 quarts of diesel rated engine oil in all of my 300s. It will take a while to get rid of the "stuff " under the cap, and you should also check the PCV valve and system for proper functioning (will help with condensation in crankcase). From what you have convayed here, in my "OPINION", you have a sound engine that will benefit from proper maintainence,and give you good service.
PS. These engines do on occasion lose a head gasket, not a major thing if dealt with when it happens. Check your coolant level regularly, and investigate any regular loss. Hope this helps, good luck. OBCB
PS. These engines do on occasion lose a head gasket, not a major thing if dealt with when it happens. Check your coolant level regularly, and investigate any regular loss. Hope this helps, good luck. OBCB
Cranky Old Guy
Joined: Mar 2008
Posts: 3,562
Likes: 6
From: Raphine, Virginia
I'd hold off on the rebuild/replacement. Clean up the engine good and find your leaks. No mention of smoke or running bad. Change out the PCV valve, check the hoses, cheap and can force leaks. Run it longer to make sure that condensation burns off and see how things go from there.
Cargo Master
Joined: Dec 2004
Posts: 2,232
Likes: 3
From: NE Texas
Those are not bad enough numbers by themselves to justify an overhaul. If the engine sounds good and is still holding reasonable oil pressure, it's good to go. The two end cylinders are the lowest which is to be expected. Under normal conditions the end cylinders always wear faster than their inner siblings.
Postmaster
Joined: Dec 2006
Posts: 3,603
Likes: 10
From: Spokane, WA
The cold starts and short trips are not the better operating conditions. More frequent oil changes and some extended running time (not idle time) may help but even at that, your compression does not indicate the need for an overhaul.
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