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  • F150 w/high hours

    I'm looking to repower and ran across an F150 with 2700 hrs for $4K.

    IMO that's a lot of hours but was told it was well maintained. It's up in Alaska so can't personally view it but did ask for a computer readout and compression numbers.
    Anything else that I should be concern about ?

  • #2
    Yeah, how ya gonna get it to Calif??? Have them video the compression test and running if they will do that .Easy with todays cameras. Still..lots of hours !

    Comment


    • #3
      I would rather have a leak down test run.
      compression test is a teat on a boar hog on a 4 stroke outboard.
      has the balancer been replaced,if its older than a 2010 or so.
      I would also pressure test the lower unit.

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      • #4
        Too many hours is also my concern. Think I'll pass on it and keep looking for something local with low hours. Thx guys.

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        • #5
          Originally posted by rodbolt17 View Post
          I would rather have a leak down test run.
          compression test is a teat on a boar hog on a 4 stroke outboard.
          has the balancer been replaced,if its older than a 2010 or so.
          I would also pressure test the lower unit.
          I was watching "How it's Made" two nights ago. The particular episode was about the building of a Porsche 911 with the horizontally opposed 6 cylinder engine.

          After the engine was built they put it in a test cell and spun it at some RPM. Purpose was to measure and monitor the air flow and pressure produced, so as to verify the health of the just finished motor.

          Now why would a company with the reputation of Porsche, with all the resources in the world at their disposal, not use a leak down test, but instead use an inferior test that is as useless as the teats on a boar hog?

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          • #6
            When same *** marriage reaches the animal world, those teats may become useful!

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            • #7
              Originally posted by boscoe99 View Post
              I was watching "How it's Made" two nights ago. The particular episode was about the building of a Porsche 911 with the horizontally opposed 6 cylinder engine.

              After the engine was built they put it in a test cell and spun it at some RPM. Purpose was to measure and monitor the air flow and pressure produced, so as to verify the health of the just finished motor.

              Now why would a company with the reputation of Porsche, with all the resources in the world at their disposal, not use a leak down test, but instead use an inferior test that is as useless as the teats on a boar hog?
              Not having seen the program, you state that they rotated the engine to test pressure and airflow.
              As I understand a leak down test is a static test, becomes meaningless or useless (as.......) when engine is rotated.
              It makes sense to me to want to test the engine without fuel. So a compression guage connected whilst turning engine does give useful information. Air/fuel does need to be compressed before setting it alight. There are pulse tuning affects that influence the actual compression of the mix.
              Those that have knowledge of two strokes would be aware that the exhaust tune pipe can easily raise the piston compressed mix a further 30 or more %.
              This would also determine the maximum combustion pressure that the engine can withstand.
              So I suspect Porsche were not that concerned whether valves, ring etc leaked.
              Notwithstanding electronic pressure sensors might have been more useful perhaps.

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              • #8
                last summer I did an F80 that some other mokaniks had messed about with.
                compression test results.
                #1 135
                #2 130
                #3 135
                #4 130.
                motor was fubar.
                bad head but all the other "mokanicks" bought it,
                leakage rate on #4 was 80%.
                head had corroded and was leaking.
                that's why on a 4 stroke outboard a koprezzion test is a teat on a boar hog.
                sent the head down to Jeff at Flagship marine,they welded and surfaced it and all was guuuud.

                the other Mokanics did not even own a leak down tester nor did they,and still don't,know how to use one.

                Comment


                • #9
                  Besides not knowing how a leak down tester works, it takes a bit more effort to check an engine than a very simple compression tester...

                  Now if your looking to buy a motor and it has a dead cylinder WITH just a compression gauge, just move on....

                  I checked the leak down on my Snapper B &S 7 HP, overhead valve mower engine (about 13 years old), at 100 PSI, I had a leak down of 2%. Basically still new internally (with one valve adjustment, and never pulled the head). I do run RF in that engine too..

                  It makes diagnosis MUCH EASIER. There's no guessing (in most cases).
                  .
                  .

                  https://www.otctools.com/products/cy...age-tester-kit

                  Scott
                  1997 Angler 204, Center Console powered by a 2006 Yamaha F150TXR

                  Comment


                  • #10
                    When an average Joe buys, how many have that gauge and air supply to perform a leak down test at the seller's location? Probably the reason a compression test is the most common.

                    Comment


                    • #11
                      its also a teat on a boar hog.
                      other than the V8 F300/350 I can do a leakdown test in about 1/2 the time you can do a compression test.


                      the reason I got the above F80 is cause of after the 2nd carb "rebuild" and the 3rd tune up by 3 different mokaniks the customer came in to buy the third mokaniks recommended ECU.


                      they asks for an ECU for that motor and I asked why they thought the ECU was bad.
                      they told me the story.
                      that's when I said: bring it to me, if its an ECU problem I will buy and install it.
                      if its not you pay to fix it.

                      compression numbers were still written on the cam cover and on all three previous workorders.
                      took less than 10 min to find the issue.
                      issue was a simple corrosion track under the head gasket allowing a slight amount of water in the cyl at idle speeds.
                      my first clue was on removing the plugs and inspecting them carefully I saw the tiny tiny green flecks on the center electrode.
                      wasn't enough to lose anything on the compression tester,was enough that at 80% leakage I knew what cylinder had the issue. and as no air was coming out the intake,none could be heard in the exhaust and removing the breather pipe showed no air past the rings it had to be a sealing issue on the headgasket area.

                      typically when a two stroke dumps compression its a massive dump,4 strokes will run a long time with a valve leak or a stuck ring. two strokes wont make a trip with an intake leak or a stuck ring,they tend to pop a piston. and its a massive compression dump.

                      Comment


                      • #12
                        Originally posted by Reel Kahuna View Post
                        When an average Joe buys, how many have that gauge and air supply to perform a leak down test at the seller's location? Probably the reason a compression test is the most common.
                        Just making a point.

                        If your fixing to drop 5, 10, 20K on a used engine either check it with a leak-down tester (I have a small air compressor and can do with a 110 outlet) or pay someone who CAN DO IT. Its your $.

                        (That gauge BTW was less than $70.00)

                        Bottom line, a good compression check will NOT guarantee a good engine
                        Scott
                        1997 Angler 204, Center Console powered by a 2006 Yamaha F150TXR

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