I know that oil pumps are the bases for discussion, but:

I do have a type for and a type 1 pump,
But I like the Idea of having a type 4 pump, that lines up and is made out of aluminum,
like this one.
http://www.cbperformance.com/ProductDetail...roductCode=1829
It has the same expansion rates like the block.
Has anyone used it?
What is the QUALITY?

I've used a CB pump before, quality and fit is hit or miss.
Ditch the POS aluminium cover and use a steel cover.

Just installed a 1829 Maxi Pump 1-914/Type 4 oil pump from CB Performance. Used Gasgacinch gasket sealer (per CB advice). Started motor -- at just under 1,000 rpm idle -- 40 psi at cold start up, declined to 27 psi with warm oil -- much improved oil pressure! BUT after warm up, checked for oil leaks, -- 3" puddle of oil on the floor under the oil pump with a new drop every 15 seconds or so.
I assembled the pump with a smear of new engine oil (along with a full engine oil change) on the two gears and their shafts, and applied the sealer to both sides of the thick gasket (pump to engine case) and the pump and cover plate mating surfaces (paper gasket is too thin to smear sealer on). By this time the paper thin gasket was oily which I attempted to remove most of the oil by blotting with a paper towel. I torqued the four bolts to about 15 ft/lb.
Oil is clearly leaking only from the pumps cover plate gasket line, as observed from under the jacked up car. I could only access the two bottom pump bolts which I was able to tighten a little more -- made no reduction in oil leak!!

Where did you get or how did you design/make a steel plate. Why was this necessary? I assume this was a good solution?
Thanks, Keith.

Further,

Just found another thread where "cary" laps a cover plate flat, then uses the thin gasket with 518 sealer. Perhaps I should try this?

Also saw that this repair likely can be done without removing the engine again. Jack support the engine. Remove the engine support bar, maybe slight modification to some of the fan rear shroud webbing, and take advantage with my pump now installed with bolts (came with the kit) after removing the studs?

You can use this cover, just plug the outlet with a 3/8" NPT plug if not going full flow. http://www2.cip1.com/ProductDetails.asp?Pr...ode=C13-31-2940
Also make sure that it's flat using a piece of glass and some 120 grit sandpaper.
I use the steel cover because the pump gears actually try to drill through the cover.

I use Threebond under the pump and on the thin cover gasket I rub RTV (gasp! not RTV! Yes RTV...) into the gasket. I said rub it in, no excess what so ever.
Absolutely important that there is no excess RTV, or any other sealant you may use, in the grove that is cut around the face of the pump.
That groove is there for a reason, to the relieve the pressure that causes cover leaks.

Thanks Mark, great info. and explanation of the purpose of the circular groove.
I assume the parts stores know what "Threebond and "RTV" are(?). I assume I will have to get both new gaskets, although the thick gasket between the pump and the engine case appears to be working and I may choose not to disturb it. Do you know if this plate comes with a gasket?
I hope I can pull the pump cover tomorrow without removing the engine again as described above. I will order the steel cover plate as you suggest and plug it and lap it flat.

i use yamabond on the cases and hylamar on EVERYTHING else (sorry doctor evil). if it still leaks, the surfaces are bad.

Threebond 1104, Yamabond, Hondabond is all the same stuff, ebay or go to a Yamaha dealer.

RTV Black well some guys give me shit for that and tell me a different product is superior...then get all pissy when I point out their superior sealant is also RTV based.
RTV has a bad rep because peeps use it wrong and/or in the wrong places.

Other sealants also work, but on the pump cover if you gob it on and block the groove failure will happen, just a matter of time.

Cover gasket is often separate but only about $1.

Cover gasket also from cipl.com?
Thanks again, Keith.

I bought a high volume type 4 from Fat Performance in Orange County California. They modified it, runs great and no oil leaks..

I recommend the Schadek 26mm (for 3 rivet cam) pump, the 30mm is too big without a pressure relief cover.
Never use a Melling iron pump, too big, but worst is the fact iron has a different expansion rate than aluminum.
But the steel cover off of a melling can be used for a pump cover.

The schadeck pump has issues as well with QC sometimes the OD of the pump is under.
I often cut a groove into the pump and install an O-ring, but they are hard to install without tearing the O-ring.
Instead of an O-ring I've also applied a small amount of Threebond in the ID of the pump hole just behind the in/out holes. Don't know if this has helped, but so far no issues doing this trick.

Just talked with CB Performance technical guy. Have an installation procedure I will try, and report back.

Just back from a drive-by to Keith's place to see how it is coming along.

He has proven to me that one doesn't need to drop the engine to service the oil pump. He is "milling" the oil pump cover plate flat on a slab of granite and sanding sheets / which clearly illustrated that the cover plate was not even close to being flat and true to seal / so therein is the source of theleakage issue.

What would be interesting to know is.... Has anyone started a 914 without the engine bar being attached. If so, and not a catastrophic jolt from inertial mass suddenly being energized,... Keith will be able to start his motor and visually observe if the oil leak is solved prior to bolting up all of the goodies dropped to get at the oil pump.

Before purchasing a new steel cover plate, L will bolt on the lapped cover plate that was badly non flat and is now true flat. Any thoughts on how much torque given that it is aluminum?

Update: thoroughly cleaned the mating surface of the pump - simple green, water, paper towels, and the face plate flattennd on wet sandpaper on glass. Carefully painted on 1/8th inch wide thin smear of sealant (Gascacinch per CB Performance) on face plate surface perimeter. Quickly and very carefully positioned the face plate on the pump and torqued the four bolts -- also carefully (10 lbs/ft?). Waited one hour. Then ran the engine for about 10 minutes at idle - oil pressure started at 40 psi dropping to 30 at warm temp. No oil leak! Took the car for a test drive - temp rising to 180, idle oil pressure at 15 psi. No oil leak! Problem solved. Thanks for your advice.

not to hi jack, mark henry, i know yamabond comes with many trade names, will bond, hondabond, yamabond and it is all the same, yamaha dealer is most convenient. hylamar used to be available from permatex, but it has been years since i have seen it. it is rolls royce non hardening gasket sealant. comes in blue or green compounds. green, i believe is for turbine applications, blue for automotive. works better than rtv, shellac or dry. just my humble opinion. in a pinch, i have used permatex aenorobic red gasket sealant with good results, available at most flaps. hylamar, i must now obtain online, i think it comes from cincenatti oh.