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Got the oil filter installed yesterday:




I've been going backwards and forwards on whether or not to install an oil filter. Initially I was intending to install one and I bought the filter, mount etc., then I started doubting whether to add the complexity of the extra hoses etc.
Originally the VW engine did not have an oil filter, the AeroVee does not have one either and many people building other VW aircraft conversions seem to be happy without one as well, so that really made me wonder.
Then I came across a post from the late Bob Hoover, on the topic he said: " Do you know of any modern engine that does not incorporate full flow oil filtering?"
Ok, that got me over the line, I'm installing a filter.
I decided to mount it to the left side of the engine mount, not drilling trough the mount or anything, just clamped in place with 3 bolts and a bracket, the pictures show better than I can explain.
I also made and installed the hose going from the oil pump to the filter. I still need to make and install the hose going from the filter to the cooler and from the cooler back to the engine, however I did not have the correct AN fittings so I'll need to order these before I can finish the job.

Anybody else putting an external oil filter on their VW?

There is nothing wrong with adding a filter, but. The Continental O-200 in my C-150 has never had a filter, since 1965 and 5000 hours of operation. I overhauled the engine at 2200 hours the last time and there was nothing wrong with it. Just a gult feeling for going 400 hours over TBO. I feel the secret to longevity is the 25 hour oil change, reccommended when you don't use a filter. With a filter they say 50 hours is required/allowed. It isn't dirty oil that is the problem, it's the buildup of acidic products from the NOX gases that eats your cam shaft. Chage oil more often and don't rely on the filter to "purify" your oil.

There are many of us who have installed an oil filter. If you notice, Sonex how has one in their web store as well. I feel better about it after looking at my bearings when I had to replace my crank recently. So, if you like the idea, do it.

Onex wrote:With a filter they say 50 hours is required/allowed. It isn't dirty oil that is the problem, it's the buildup of acidic products from the NOX gases that eats your cam shaft. Change oil more often and don't rely on the filter to "purify" your oil.

Many air-cooled engines in older aircraft and VWs have run a good numbers of hours without a filter. I have a filter on my Corvair and like having it there as it can catch small items that could do damage if left unchecked. But your point about oil is extremely valid and changing oil often is the right thing to do. Even with my filter I still change oil at 25-30 hours. I heard a very wise engine builder say, "the cheapest parts you will ever put in your engine are gas and oil ... and BTW they are the easiest to install."

Welcome to 2015!

Dale
N319WF

rizzz wrote:Then I came across a post from the late Bob Hoover, on the topic he said: " Do you know of any modern engine that does not incorporate full flow oil filtering?"

Does any modern engine require oil changes every 25 hrs?

radfordc wrote:

rizzz wrote:Then I came across a post from the late Bob Hoover, on the topic he said: " Do you know of any modern engine that does not incorporate full flow oil filtering?"

Does any modern engine require oil changes every 25 hrs?

True.

There have been numerous reports of people with Aerovees and other VW conversions using external oil filters who have blown the oil filter seal and or oil line to the filter. Sonex firmly warns against an external filter. The oil filter sold by Aero conversions is for use with the Aerovee turbo and sits inside the engine sump.

Anytime you make a modification to your engine, especially one warned against by Sonex you are taking a huge risk.

For me, I want my flight risks to be as low as possible.

Hi, I wasted about 400 bucks trying to install an oil filter and oil pump from CIP on my Onex and about a month of trying different filters including the HP-1. I couldn't get the filter to seal on the mount, kept blowing by. Not sure if the CIP pump just put out too much pressure or the mount was of poor quality. I did install the internal filter which seemed to work ok.

All I can say is good luck if you’re using parts from CIP.

SonexN76ET wrote:There have been numerous reports of people with Aerovees and other VW conversions using external oil filters who have blown the oil filter seal and or oil line to the filter. Sonex firmly warns against an external filter. The oil filter sold by Aero conversions is for use with the Aerovee turbo and sits inside the engine sump.

Anytime you make a modification to your engine, especially one warned against by Sonex you are taking a huge risk.

For me, I want my flight risks to be as low as possible.

My engine has a Gene Berg oil pump cover with pressure relief valve which should prevent this from happening.

Slightly off topic, but I was not aware Bob Hoover had died. Google does not mention it. Does anyone know the date?.