Help!!! Getting ready to pull the old flathead out and check it over and re-do the valves while it snows. Thinking about converting it to a full flow oiling system. Got some dumb questions since I've never done it before and no one I know has either. The engine is a 59 block. From what I've read there are two different methods to do this. One involves drilling the back of the block and plugging an existing hole. This system gives you filtered oil to everything except the rear main. The second type involves a special oil pump with a hose that exits the pan and delivers filtered oil to everything. The second sounds the best, but would definitely take away some of the nostalgic look that the first one would not. Now to the questions. (1)Has anyone had any problems with their system and which one is it? (2)How much was the oil pressure reduced with your system? (3)Who did you purchase your system from? (4)About how long does it take to build oil pressure when you change oil? (5)Does your oil stay clean now? Appreciate any and all answers to the above questions and anything else you can think of. Thanks..... rumble seat

RE: full flow oil filtering I don't have any experience, but Red Hamilton at Red's Headers has a third alternative which filters 100% of the oil and isn't either of the two mentioned techniques. He sells the plans and kits to do it (supposed to be cheaper than Motor City), but I don't know how it works and I haven't seen it installed.

Bubba (Nov 17 1999 6:41PM) RE: full flow oil filtering I have the special oil pump/thru-pan system on my 59L. It's from Motor City Flathead in Dundee, Mich. Oil pressure builds instantly. Runs 40 psi at idle on the hottest days and typically runs 60+ psi at speed. Keeps the oil as clean as my '96 GMC does. The only problems I had with it include: It uses the push-on hose fittings instead of clamp-on (mine blew off and damned near ruined the motor). And, I had a slight seeping of oil around the thru-pan fitting, which I solved with a little judicious use of RTV Blue silicone sealant. Other than that, it's been just peachy. Is it better than no filter or stock part-time filter? That's been debated with stong arguments on both sides previously on this board.

RE: full flow oil filtering Rumble Seat: I have the full flow system on my 50. Have had no problems with it. I run about 40-45 pounds of oil pressure at idle, even when hot. I got the system from Motor City Flathead. Then installed it during a rebuild. (1-734-529-3363). When I change oil it takes about 20 seconds to build oil pressure. Note of Caution: Do not fill the filter with oil when you change it. I tried this in an effort to build pressure sooner and ended up with a hydraulic lock and no pressure. Let the new filter fill on it's own. As to the oil staying clean longer, I don't know yet as I am still breaking in this engine. It does appear to stay cleaner longer but time will tell. My personal opinion is that it is a great improvement over the original system and I'm glad I did it. Also makes it easy to change filters. Uses a standard spin on filter. (Fram PH8A) The last catalogue I have lists it $189.00.

JWL (Nov 17 1999 9:45PM) RE: full flow oil filtering Red has 3 options available. The plans alone are available at $20. The plans and parts are $99. All the above with finned aluminum housing is $244. You can contact them at They are very pleasant and helpful people. Typical Flatheaders.

Dave F. (Nov 17 1999 11:58PM) RE: full flow oil filtering Went with the cheapest of all the options. Cost for the conversion will be less than $50 when complete. This is the version where a hole is drilled and tapped into the rear of the block next to the raised boss the original filter was connected to. A plug is set in the original passage within the raised boss to redirect the oil flow to a modern filter and then returned through the new hole. As the oil passage to the rear main is at the base of the raised boss, the oil to the rear main is not filtered. Uses a stock oil pump. Haven't completed assembly yet so don't have personal knowledge on how well it works, but it's a clean and easy approach to near full flow filtration.

Paul Selfe (Nov 18 1999 6:25AM) RE: full flow oil filtering Rumble Seat, I have the MC system on the 8BA in my roadster. I use Castrol Syntec (blend) and the idle pressure stays around 40, at speed 60-75 psi. With the blend oil, it stays cleaner longer, and almost never any vapor, even after a 30 mile run (that's long for my area). Everything is exposed to view, and I want it to look nice, so I have chrome cover on filter and stainless sheath on the lines. I have never had a leak anywhere, and I am very pleased with the system

philbill (Nov 18 1999 2:56PM) RE: full flow oil filtering i use system all home made that was in amer rodder several years ago befor kits to do same....uses aviation type fittings brased to oil pan and lines to ph8a filter mounted on fire wall...every drop of oil that goes thru system passes thru filter....never had problems with oil pressure etc....oil get dirty as ever but this is due to splash system to cyl walls which we all have to deal with and common to all of dirt depends on tightness of least you have piece of mind that nothing but oil is getting to the internals of your belovid motor,,,also note this system requires knowledge of welding and braszing works well for me philbill

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