jeepsr4ever
I realize the internet is a wealth of good information however it is also a place where lies can be perceived as truth.
I recieved a personal message from a member here pertaining to an issue we are having between a mfg and a mfg. This discussion involves our R&D on the oiling system and on high flow oil pump gears.
In march of 97 we created a high flow oil pump gear to the tune of 22% over stock. This gear was form cut from 2320 aluminum and made in many variations from helical, longer than stock and with more and less teeth. We even tried many different variation of dimension and material. We had the gears dialed in as close as possible without binding occuring when the temperature rose to operating temp.
Our findings let us down...we found that sluggish starts in winter and excessive distributor gear wear was happening with these gear sets. Even with teflon coating these gears would cause problems and wear rapidly in normal conditions. The project was finally scrapped in april of 2003. Bulltear high flow oil pump gears sets would never see the light of day.
Our problems
1. the distributor gear and cam gear at a maximum tooth contact werent designed to handle the load.
2. The expansion rate between cast 356 aluminum and any series of billet aluminum including 7000 series was too far from each other an always caused either binding and rapid wear or rapid wear casue by excessive clearances
3. In the AMC oiling systems the pressure relief spring would open and sometimes stay open and not relieve enough pressure also causing excessive distributor gear wear
4. The oil filter bypass would open due to the over pressurized area betwen the oil filter and oil filter adaptor causing dirty oil to enter journals and bearings
5. Even tweaking the gears down to .0003 wasnt enough to halt the major bearing and distributor gear wear
It was our mission to combat wear in the pump after the spring rates were found and the inneficiencies were discovered we found the stock pump to be quite adequate when it was in tolerance. We tried many different coatings....titanium, copper, chrome, hard anodize, ceramic, nickel and electroless nickel. We also took old covers and bored them over installed oil lite bushings and stainless steel inserts. We also tig welded the covers and re machined them back to spec. After alot of testing and rigorous and expensive coatings we found the best method was the tri-cloro and electroless nickel plating. This plating adheres to the nickel and we have tested it to 450 degrees to which it hardened to 52 rockwell (very hard!) We have never had a failure of a nickel coated timing cover and have never had any nickel flake off. We did have a customer who ate 3 sets of distributor gears (caused by the distributor) and subsequently wore off a small amount of the nickel coating. This customer sent the cover back to us and the distributor and we found the fault to be in the distributor and fixed it for free for him. The nickel timing cover after taking 3 sets of gears was well within spec. We gave him a free replacement and are using him old timing cover on a rebuilt engine.
We have done alot of R&D on this situation and have dumped many ideas and man hours into the final product. The personal message I recieved this morning shocked me and made me also chuckle.
I was sent information from a member of the amcforum.net. We have many members here who are also members of the amcforum.net. The amcforum.net is a primarily drag racing and tech resource for many AMC fans on the internet. The information I recieved was of a member who is selling aluminum oil pump gear sets. Now some members here have purchased these gear sets and have had either distributor gear wear and destruction or oil pump binding. The perosn associated with these has also had distributor gear wear although I am not sure what caused this..speculation only tells me his own gears caused this problem. We have sold many a nickel cover to his customers who have used the gears and had theirs destroyed. I told him the dangers of this type of setup and never got much of a reply. I also told him we already tried this. Today he called the nickel coating flawed in the matter that it would float on the aluminum after thermal expansion. He also claimed that I tried to get his magic formula from him. Nickel doesnt not float on cast or on most materials. With engineering background I can honestly say that the nickel doesnt float and I find his allegations of my trying to get his "magic" formula absurd. I dont understand this but it is closing on winter and he must feel safe posting in a area that I do not have access to reply to. We have sold alot of these covers with zero problems and zero "nickel float" or peeling of any kind. Some of these covers were tested to 450 degrees so his basis for fact is only speculation. We however did make aluminum oil gears and controlled to size to .0003 before installation. I doubt his machinist has played and tweaked the numbers like we have...if he did and if they had the expertise rather than relying on concept then their findings would be that aluminum gears in any series of aluminum isnt a good candidate for the AMC oil pump including the 7000 series aluminum. Could also be that this guy needs to sell these as fast as he can and is willing to step on toes to do so. Lies I will not contend with however. All this from a guy whos partner called the rictor scale a measurement for hardness and also claims you can put a fuel pump eccentric on backwards.
Normally I do not get nasty or call someone out but when I recieve false information you better believe I will do my best to fix it.
-MC
