At 02:29 PM 10/8/98 -0400, William M. Gilroy wrote:
>My 77 Midget (1500 engine) has an oil leak down low
>by the dipstick. I thought it was the pan gasket.
>After I put in my new dizzy I found that I was leaking
>even more oil. I found that the oil is not coming from
>the pan gasket but from the dipstick hole. I checked
>the oil, it is full but not over full. The valve
>cover vent is not plugged. I still get the leak if I
>run the engine with the valve cover vent disconnected
>from the carb. at the valve cover. Now I figure that the
>problem is excessive crankcase pressure even though the
>the crankcase is vent is work. I then ran a compression
>test and these are the number I got:
>
> Cylinder 1: 135 psi dry / 155 psi with oil
> Cylinder 2: 40 psi dry / 60 psi with oil
> Cylinder 3: 75 psi dry / 90 psi with oil
> Cylinder 4: 135 psi dry / 170 psi with oil
>
>I ran my compression tests with all of the spark plugs in, and
>I squirted a couple shots of 20-40W engine oil into the cylinders
>for the tests with oil.
>
>Now I am wondering what are my options. I think they range
>from a complete rebuild to doing nothing. I would like something
>in the middle. First exactly what do these number tell me?
>Like cyl 4 is it just a set of bad rings and cyl 1 is a set of
>bad valves and maybe rings. What is the correct answer?
>What are good numbers for compression? What would I see on a
>newly re-built motor? Could I get away with just re-ringing the
>pistons and a valve job. I am trying to explore my options. I
>would like to avoid a full engine rebuild at this time.
>I can see where that would lead me to many other things (hotter cam,
>paint the car since the engine is out, weber, headers, etc.) and
>I currently don't want to do all of this stuff. Maybe down the
>road but not now if I can avoid it.
>
>Thanks in advance,
>
>Bill
>--
>Bill Gilroy
>77 Midget
>E-mail: wmgilroy@lucent.com
>Telephone: 732-957-4775
>Fax: 732-957-4775
>
> Hello Bill
Remove all the plugs. Pour one tablespoon of 30 wt oil into # 3
cylinder. Screw your compression tester into #3 spark plug hole. If the
compression comes up to around 130-175, you have worn
rings-pistons-cylinders. If there is no change, you have burnt -worn valves.
If the oil blows out the #2 spark plug hole, you have a blown head gasket or
warped head.
Sam Haynes
TR3 Original Owner
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