oil coming out of dipstick hole

All Models and Years
dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

oil coming out of dipstick hole

Unread post by dick2256 » Sun Apr 09, 2017 3:20 am

was running good until yesterday and the weather got to 75 and fresh oil coming from dipstick hole

User avatar
lostboy
Posts: 341
Joined: Mon Nov 09, 2015 2:59 pm

Re: oil coming out of dipstick hole

Unread post by lostboy » Sun Apr 09, 2017 4:34 am

Sounds like excessive crank pressure which isn't good. Not 100% sure though. Probably time for a compression and leak down test.


Sent from my iPhone using Tapatalk
1961 Corvair 700 Sedan (80hp 3spd Gasoline Heat)

User avatar
toytron
Posts: 451
Joined: Mon Dec 28, 2015 4:30 am

Re: oil coming out of dipstick hole

Unread post by toytron » Sun Apr 09, 2017 4:45 am

Check your crankcase ventilation

Ed Stevenson

Edwin Stevenson
Industrial Electrician
Electronics Technician
65 corvair corsa convertible turbo
65 corvair monza

User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 7033
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: oil coming out of dipstick hole

Unread post by bbodie52 » Sun Apr 09, 2017 5:06 am

Since your boat engine is equipped with an alternator, I'm assuming the engine is from a Late Model (1965-69) Corvair, and is fitted with a Positive Crankcase Ventilation (PCV) system. On any engine it is normal to have some combustion chamber pressure and fumes leak past the piston rings and enter the crankcase (which is sealed). A breather tube from the engine crankcase top cover provides a ventilation path for these crankcase fumes. The PCV system is a metal tube that exits the top shroud and connects to the air cleaner. A side tube connects from this tube via a vacuum hose to the vacuum balance tube that is connected to the intake manifold at the base of each carburetor. This vacuum tube and hose is the only way for crankcase pressure to vent, as the fumes are drawn back into the intake manifold.

There is a small fixed orifice hole in the PCV tube, where the rubber hose is connected. This fixed orifice limits the amount of vacuum that can pass from the crankcase to the intake manifold. It tends to get clogged and must be cleaned periodically. If it becomes clogged the crankcase pressure will build up with no place to go. The pressure buildup will often exit the oil dipstick tube, and will force some oil out with the pressure release.

The PCV system can handle normal crankcase pressures. Try cleaning the PCV fixed orifice and see if your problrm goes away. If this effort fails the crankcase pressure may be excessive -- normally caused by worn or faulty piston rings in one or more cylinders. If this is suspected, a compression test and possibly a leakdown test (as previously mentioned) may be needed.
Brad Bodie
Lake Chatuge, North Carolina
Image

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Mon Apr 10, 2017 6:29 am

getting a lot of blow by from the crankcase vent tube so probably have a burned piston it looks like what I had years ago after number 6 burnt a hole
in my first engine.
I'll check the compression and see what I can find out but would rather find a different motor
going to check around here in Iowa and see if there are any for sale

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Mon Apr 10, 2017 1:34 pm

I haven't had time to run a compression check but I have this other motor with 5 good pistons and nearly new rings
and bearings and am wondering if you can tell with the number inside the piston 3819699 if it would fit in my 1965 this other motor was in a 1964 convertible that had just been overhauled but he drove it to Texas and fried one of the pistons it was also A 110HP but I am not sure which engine
I can't find any numbers on the block

User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 7033
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: oil coming out of dipstick hole

Unread post by bbodie52 » Tue Apr 11, 2017 8:47 am

Engine cases usually have an engine serial number stamped near the top cover mounting area, near where the oil filter adapter mounts...

Image

Image

The suffix letters at the end of the serial number can help to identify the engine.

1964 164 CI Engine...

YN or VB = 110 hp Manual Transmission
ZF or WB = 110 hp Auomatic Transmission
YM = 110 hp Manual Transmission with A/C
ZG = 110 hp Auomatic Transmission with A/C

If your engine is a 1964, the outer diameter of the cylinder barrels would be 3-3/4" (where they insert into the cylinder head). In 1965 and later the cylinder barrel outside diameter was increased to 3-13/16", which increased the cylinder head to cylinder barrel head gasket sealing surface area. Otherwise, the 1964 cylinder barrel design (with the notch at the bottom) and the piston/connecting rod design in 1964 was the same as 1965-1969).
Brad Bodie
Lake Chatuge, North Carolina
Image

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Tue Apr 11, 2017 2:01 pm

Brad
my engine has a number T0219RH
and the other engine has a number T0506ZF
so do you have any idea what year mine is?
I am sure getting confused

User avatar
terribleted
Posts: 1777
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: oil coming out of dipstick hole

Unread post by terribleted » Tue Apr 11, 2017 2:32 pm

Your RH engine is coded as 110HP Powerglide from a 65-68 car. Your ZF engine is either 60-63 98-120HP w/powerglide trans or a 64 110HP w/powerglide trans.Reading the numbers on the ends of the heads themselves will determine what they really are. The numbers are located stamped on the rear face of the right head parallel to the rear side of the valve cover, or on the same spot on the front of the left head. These numbers are somewhat obscured by the factory exhaust hanger on the right side and the heater outlet shroud on the left head. They are 7 digit numbers. On your airboat these numbers might be in plain view:)
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Tue Apr 11, 2017 3:37 pm

Ted
the motor on my airboat heads are 3856759
and the numbers on the other motor heads are3856632
so can you tell me what I have from that?
I really appreciate your help

User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 7033
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: oil coming out of dipstick hole

Unread post by bbodie52 » Tue Apr 11, 2017 5:29 pm

dick2256 wrote: Tue Apr 11, 2017 5:37 pm
the motor on my airboat heads are 3856759
and the numbers on the other motor heads are 3856632
so can you tell me what I have from that?
3856759 = 1965, 164 CI, 110 hp, 9:1 CR, 3-13/16" Cyl. Bore (into head)

3856632 = 1964, 164 CI, 110 hp, 9.25:1 CR, 3-3/4" Cyl. Bore (into head)


The piston and connecting rod should be transferable, but the cylinder barrel outside diameter would be a mismatch.

The above specs are from the CORSA reference that I have attached.
Attachments
CORSA Corvair Technical Guide 1+2 - Corvair Code Numbers.PDF
CORSA Corvair Technical Guide 1+2 - Corvair Code Numbers
(1.25 MiB) Downloaded 11 times
Brad Bodie
Lake Chatuge, North Carolina
Image

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Wed Apr 12, 2017 3:03 am

how do I do the leak down test
and what should my compression range be

User avatar
bbodie52
Corvair of the Month
Corvair of the Month
Posts: 7033
Joined: Mon Aug 06, 2012 12:33 pm
Location: Lake Chatuge Hayesville, NC
Contact:

Re: oil coming out of dipstick hole

Unread post by bbodie52 » Wed Apr 12, 2017 5:51 am

The compression test specification is 130 psi at cranking speed, throttle wide open. Maximum variation is 20 pounds between cylinders (see the attached shop manual section). The procedure is outlined on page 6-3. If the results reveals low compression in one or more cylinders, a leakdown test can be performed to measure leakage and the percentage of pressure loss into the crankcase. Beyond that a physical examination of the piston, rings and cylinder would have to be performed to determine the corrective action.

If the engine suffers from excessive blow-by that is leaking past one or more pistons, you will see the result exiting via the road draft tube on a 1960-62 Corvair, or the PCV system on the later cars. A damaged piston, damaged piston compression ring, or damaged cylinder barrel can be the cause. A cylinder compression test or leak down test may reveal one or more bad cylinders. A compression test simply inserts a compression gauge into each cylinder, one at a time, and cranks the engine with the throttle and choke wide open to determine the maximum pressure that can be developed in each cylinder on the compression stroke (both valves closed).

A cylinder leak down test is a more advanced diagnostic procedure, and little more difficult to perform, because it requires some fabricated plumbing or a special test instrument, and a large capacity air compressor. Each cylinder to be tested is set at Top Dead Center (TDC) on the compression stroke (both valves closed). External air pressure is applied through the spark plug hole, and the percentage of leakage is evaluated. The source of the leakage (intake valve, exhaust valve, cylinder head gasket, or piston/cylinder seal) can be determined using an automotive stethoscope to listen for the leakage path (intake manifold, exhaust manifold, or crankcase). This test is performed on each cylinder, to determine the mechanical seal and condition of each cylinder. A video demonstration of this process (in this case, using a Volkswagen engine) is shown below.



For comparison, there are many leak down testers available on Amazon.com. An example is shown below...

Image

OTC 5609 Cylinder Leakage Tester Kit

4½ Stars out of 5 with 94 customer reviews | 5 answered questions
List Price: $109.95
Price: $66.12 & FREE Shipping.

Prices ranged from $30.99 to $123.86 with 11 LEAK DOWN units listed.

:link: http://www.amazon.com/s/ref=sr_st_revie ... eview-rank

A decent mechanic's stethoscope can be had for about $15.00...

Image

Also helps to locate noisy idler bearings, blower bearings, etc.

OF COURSE, A PURCHASE OR A RENTAL WILL DO YOU NO GOOD IF YOU DON'T HAVE ACCESS TO A DECENT AIR COMPRESSOR WITH ADEQUATE CAPACITY.
Attachments
1965 Corvair Chassis Shop Manual - SECTION 6 - ENGINE TUNE-UP.pdf
1965 Corvair Chassis Shop Manual - SECTION 6 - ENGINE TUNE-UP
(2.92 MiB) Downloaded 6 times
Brad Bodie
Lake Chatuge, North Carolina
Image

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Wed Apr 12, 2017 11:59 am

ok here are the results of the compression test
1=75#
2=150#
3=135#
4=90#
5= 0#
6=95#
I am guessing rings would fix all but number 5 and I bet it has a burned position
I am not sure what I want to do yet I may pull the head off of the 1-3-5 side and check the valves on number 5 and also the piston
last time I had it on the river I was only tacking 2800 rpm and it should tack out at 3250 which is controlled by the prop pitch and length
if I replaced the rings in all cylinders would that put extra pressure on the crank bearings?
the first one I tried was number 5 and that zero reading made me wonder about my new compression tester was any good but the next one showed it was ok

User avatar
terribleted
Posts: 1777
Joined: Sun Apr 18, 2010 2:36 pm
Location: Atlanta, GA
Contact:

Re: oil coming out of dipstick hole

Unread post by terribleted » Wed Apr 12, 2017 1:46 pm

OK so #5 is zero. Have you looked closely at the #5 rockers arms and pushrods. Does everything appear normal. Any noise from the #5 cylinder area? You could have a dropped valve seat or issue in the valve train holding a valve open (stuck lifter or valve??) Remove valve cover and investigate inward until you find the problem. Try loosening the valve adjustment on #5 to see if you can get compression that way (lifter over adjusted or stuck long holding valve open on release??). Pays to start with easiest stuff and move deeper as you investigate. If you are very lucky you might not need to pull a head, but, I think you probably will need to.

Your compression readings have more variation than is ideal. This might not be an issue (except for the zero) Particularly If the engine has been sitting for a while and these reading were taken cold, the lower numbers may come up with a few operation cycles. A zero will not generally recover. When I see consistent numbers under 90 or so after a couple operation cycles I think worn engine rebuild. 100-150 is where most good vair engines read. I like to not see more than 20% variation. Compression reading can be effected by incorrect valve adjustment as well.
Corvair guy since 1982. I have personally restored at least 20 Vairs, many of them restored ground up.
https://www.facebook.com/tedsautorestoration/

Located in Snellville, Georgia

dick2256
Posts: 117
Joined: Wed Dec 10, 2014 10:05 am

Re: oil coming out of dipstick hole

Unread post by dick2256 » Wed Apr 12, 2017 3:05 pm

the engine has set 3 days since it was last run I ran several cycles on each piston with the starter
the tech guys on Clarks corvair said to pull the heads and see what I can find they said I only had two good pistons and the rest are way to low
my problem is age I will be 85 in December and I enjoy running our river so I think I will go ahead and spend the money for a few more rides
still searching for a good motor here in Iowa

Post Reply

Return to “Ask your Mechanical Questions here”

Who is online

Users browsing this forum: No registered users and 1 guest