oil coming out of dipstick hole

dick2256 · Post by **dick2256** » Fri Apr 21, 2017 7:10 am

that makes sense Ted, ok they are standard 3-7/16 try not to get mad I ask a lot of dumb questions because I am not a mechanic
I am going to pull the other head off and check that number 1 cylinder so why don't I buy a complete set of rings and ring both sides
not sure how to cross hatch honing but they say I need to do that.
I found a old guy that has a machine shop and am waiting for a price on him repairing stripped spark plug threads but haven't heard from him yet.
,

Post by **terribleted** » Fri Apr 21, 2017 7:31 am

Measuring is key too a functional lasting repair. Cylinder to piston clearances must be right or things wear out very quickly. Not mad was simply short on time yesterday:)

dick2256 · Post by **dick2256** » Sat Apr 22, 2017 5:20 am

I am not going to open the crankcase going to hone the cylinders
clean the ring grooves and put it back together
do I need to worry about the ring spacing

Post by **terribleted** » Sat Apr 22, 2017 9:50 am

The gaps need to be in the proper positions when installed. With the top op the cylinder as 12:00 the bottom oil ring is positioned at 1:30, the upper of the 2 oil rings is positioned at 10:30, the bottom compression ring is at 1:30, and the top compression ring is at 10:30. Be sure not to turn the rings over...many rings have a top and bottom. The ones that do are marked sometimes with a dimple and sometimes with a colored mark on the top surface and sometimes just a contour variation that is referenced in the instructions that came with the rings (usually such marked rings are the top compression ring, but, I seem to remember one rings set I used in the past had a specified top on both compression rings). The compression rings are also not the same part for the top groove and the bottom groove....hope you kept track of which was where and which side was up. All rings should be returned to the cylinder and position that they came from.

dick2256 · Post by **dick2256** » Sat Apr 22, 2017 1:29 pm

I am putting new rings on all 6 pistons
I haven't removed the old rings so all are where they were
is it best to remove the piston from the rod install the rings on it and put it in the cylinder leaving enough room to connect to rod

Post by **terribleted** » Sat Apr 22, 2017 3:13 pm

Connecting rod pin is a press fit. I have never removed a rod to install rings. In fact you install the rods to the pistons and then install the rings. You take your rod and piston assembly (removed rom the engine) and install the rings on the piston. You then install you ring compressor to the piston , place the piston in the top of its cylinder noting correct orientation (which way is up? Piston ring gaps must be positioned properly and there is a forward mark on each piston as well) and tap the piston down into the cylinder. Remove ring compressor and re-install piston, rod, cylinder assembly to engine. If you are planning on re-ringing without removed the piston/rod assemblies the procedure is similar except you use your short ring band type ring compressor and install the cylinder down onto the installed piston.

Re-measure after honing to be sure your piston skirt clearances are still within the .0011-.0017" spec. If over sized get a new cylinder that is not. make sure your new rings are gapped properly as well. Installed gap on the oil rings should be .015-.-55" and on the compression rings .013-.025" Smaller is better, filing of rings sometimes needed. If the gaps are larger than the spec. then the cylinder is oversize or the rings are defective or wrong size for cylinder

dick2256 · Post by **dick2256** » Sat Apr 29, 2017 3:42 am

after honing the cylinder how do I measure the skirt distance
just put the piston in the cylinder and measure with a feeler gauge ?
I sure do hate to ask dumb questions but I want to do it right

Post by **bbodie52** » Sat Apr 29, 2017 7:41 am

As shown beginning on page 6-46 of the attached 1965 Corvair Chassis Shop Manual - SECTION 6 - ENGINE , a dial indicator is used to check cylinder walls for taper, out-of-round, etc. Fitting of piston rings, measuring ring end gap, etc. is also carefully described. The shop manual is your "bible" and following the engine assembly procedures described in this section is very important. I have also found numerous Corvair engine assembly videos on YouTube that may be helpful.

Piston to cylinder clearances are a calculated measurement, as described below (assuming you have access to the correct precision measuring tools).

http://corvaircenter.com/phorum/read.ph ... 830,page=4

gnvair wrote:Date: April 05, 2017 05:04AM

The correct way to measure the piston to cylinder wall clearance is to take an outside measurement of the skirts at the correct spot and then take an inside measurement of the cylinder bore. Subtract the piston measurement from the bore measurement and you have your clearance. Typically you measure all the pistons and all the bores and match them to achieve the "ideal" clearances.

I know some people will put the piston into the bore and stuff feeler gauges down there to measure. I suppose that would "work" but it definitely isn't as accurate.