On my Ryobi BC 30 I have done a compression test and the pressure will not hold.

The compression is all over the place , Do the following To find the problem . remove all spark plugs , hold the throttle open while testing , compression test all cylinders one at a time and note the compression make sure the battery is fully charged , that is called a dry test, now do a wet test , add a teaspoon of oil to the cylinder you are testing and compression test, note pressure against dry test, if the pressure is unchanged the valves need attention ,if the pressure rises the piston rings are worn or stuck .

duplicate

check thermostat operation and have a flow test done on the radiator to check for core blockages.. For the pressure have a compression test done to determine if head gasket or cracked head

3.1 or 3.4L engine> and 3sp. or 4sp A/T?
ahhh double posted with year....... good.....
wow, the 1 in a million post with country , I salute you ! You are SaVVY.
in usa any ASE shop here, can do trans diagnosis. any.
On car tests. there are like 6 tests.
this car may have a TCM, the TCM is the transmission brain.
It does all shifting.
ill look yours up. now.... at alldata.com
btw 1: slip kills a transmission bad, dont let it slip , be gentle.
first blush, oops there are 2 A/T 3speed and 4. so? which is it?
2nd blush get the fluid changes and filter, inside, a clogged filter drops
the pump pressure, and it can slip. if pressure in not at spec.
one tranny option is the 4T-60E, (E means tranny brain shifted)
electronic shifted.
and the PCM contains that TCM brain (integrated it is this year)
has 2 shift solenoids, and 2 TCC sol. and one temperature sensor
so if you have this trannny, SCAN the PCM'
with any scan tool
there are about 30 error codes, DTC.
P0751, to P1870 (slips codes)
use a scan tool that can see, and read, ford factory Codes P1xxx.
there are other tests. ask.



my jokes on BC.
bc, = Brit Columbia not Baja Calif, (book ends, BC )
but surrey nails it.

A compression test is only a partial diagnostic. You should have a cylinder leak down test done. Low compression could be valves, Rings, head gasket or cracked head or block. IT could also be nothing depending on how low it is. So a cylinder leak down test tells you which one it is. The mechanic hooks a pressure hose to the spark plug hole, air pressure is put in the cylinder when the valves are closed. The location of the leak can then be heard.

have a compression test to eliminate head gasket and cracked head. Have a flow rest done on the radiator to check for blocked cores. Have the radiator cap tested to hold the correct pressure in the radiator.

have a coolant pressure test done to determine for leaks in the system. have a compression test done to determine head gasket or cracks.. Check radiator cap is holding the set pressure and is opening to admit water back from the reservoir on cooling. Check hose from radiator to reservoir is tight with no cracks in it.

have a cooling system pressure test done to check for leaks. have a compression test done to check for head gasket or cracked head. Have a flow test done on the radiator to check for blocked cores. Have a pressure test done on the gearbox to test for proper adjustment of bands and clutches.. Run fault codes to see if any sensors/servos have failed.

Have a compression test done to check for blown head gasket. Have a coolant pressure test done. This will pinpoint the problem

Are you using any water as far as driving does the temp gauge go up higher than usual,, as the last one i done was a loose head bolt and wasent tightened up in correct way and 1 was only tightened up twice and they missed 4 left from the rear and allowed the gasket to bypass compression gasses into the coolant system ,which done the same as yours ???.
but pumping up pressure in cooling system is about 20lbs max and the engine compression is more than 110lbs thats why,.,.,.,
Let me know how you go . RON