Main bearing pictures

Seven - 210mph runs. Turbo combo. V bearings on mains and rods. Rods look like new mains look like this.




I just read an older thread and Mike Canter mentioned that a M main with a V rod bearing is a good package?



Input and opinions?


Thanks

 

looks to be a oil and clearance problem

 

also was this line honed?Dave

 

That is interesting as when looking at the bevels on each side of the bearings they appear to be good as far as not being smashed or pushed out of shape----------- is this a wet sump or dry ?
Main bearing to crank clearances ? How much oil capacity ? What do the crank journals look like ?

I have run a mix of V's and M's bothways on the mains with no issues. Oil type and weight ?

 

Posts:2,411looks to be a oil and clearance problem


x 2
note the distorted bearing ends noticably on 2nd from bottom and slight on next one up

 

00375 clearance on the mains , 65 psi at idle and 140 psi at 8300rpm , brad penn strait 50w . Main journals look fine . To much timing pounding out the mains ??*

 

That's my point, they are not pounded out------- if they were the bevel on the edges would show distortion , flattened surfaces, Do you have a computer on the car, is there a sudden loss of oil pressure at after the finish line ?

Do you install the bearing shells in the caps dry---- nothing on the back of the insert or the cap itself ?

Wet or dry sump ?????????????? Have you thought about a 70 weight synthetic ? Where do you buy those bearings ?

 

Dry sump. This was the speed pro 142M bearing from last year. 12 hits on these. He made a change to clevites ms1795v bearing, no squish but now the flake. So ya, the clevites V stayed close to spec (original pic) but are now fracturing.

They are dry on the shell, but coming off they have a film of oil on em.. Smell funky as well, but not sure if thats from the T bones and beer after hurting the motor

 

I'm not sure about the 65lbs at idle deal and 140 at 8300--------------- if you are running a dry sump hemi with a P+P pump ?? Something is not normal as your pressure should be closer to 125 at idle and 140 at 8300 typically--\

Since both bearings are showing distress what is the rest of your setup---- how many quarts of oil do you carry during the run--- whose block, are you running a separate line to the rear main----- where and how many filters do you run ?????

As long as you put the bearings in dry, the oil film after running them is ok.

 

Dailies engineering 6 stage pump 1.6 gear with a Keith black block .Three pickups in the pan , one in valve cover and one in distributer hole ( jesel vertical distributer ) System holds 11 litres .The oil filter is a remote k/n large filter with #12 in and out to the side of the block

This is a EFI turbo engine so it idles around 850 RPM thats why the pressure looks off . I could easily turn the pressure up in need be .

 

Does the end play stay the same as you find the bearings like this or are the thrust faces of the center main damaged also ?

 

Thrust bearing is not happy on the shoulders

 

Do the top inserts look like the bottoms in the pics ?

 

Tops are used but not scary like the bottoms .

 

Have you ever tried more oil pressure ? I know that's not always the answer, and you need to be careful that you don't pump the tank dry, volume wise.

I ran a Fuel Donovan with the same clearances, cast aluminum block, billet crank, M bearings as the V's weren't available, I ran 150 at idle, 2700 rpm, 175 down the track--------- Any less pressure and the bearings looked worse for wear--- it was a Aviad dry sump setup , three stage scavenge.

To me it looks they are starved for oil at some point along the run------- very well could be after the finish line too--------

Do you have a on board data logger or a oil pressure gauge to know if it's losing pressure for a period of time ?

 

bearings

Looks like the crank is bent or broken.When was the last time the block seen a line hone?

 

Based on the pics, are you having some crank flex and bottom block walk possibly?

 

agree with tol

had v mains lower look like this a few times on several different blocks kbs,most recently last week ,main cap was broke (alu 7075) that is what I feel was what was happening when the bearings pop spots out like that,not saying your caps are broke yet but they might be moving/streching etc. two other blocks that had alot of runs on was seeing a bearing pop like that,new caps and line hone has fixed those looking bearings for me. main caps fatigue so we are replacing them before they break now.70wt brad penn 80lbs idle works for me.hope this helps,