MrDelSol253

so i have a D15b7 Y8 Mini me swap in my 94 Honda DelSol & Long story short i went thru a rebuild and 20 miles into the break in period i got.......The Knock.... Anyways i tore that **** apart (Pulled the pan, tranny, and crankshaft, etc..) and found that rods 2 and 4 both spun bearings and the bearings were both completely melted and as for the crank journals.. well lets just say they've "Officially been chopped and screwed".

I Have a new crankshaft coming tomorrow morning with new bearings and thrust bearing but how do i make sure i dont get the knock again???

p.s. i have the block in my car still, cylinder head and tranny are pulled as well as the pan and crankshaft.

BryanM.

iTrader: (1)

The Y5/Y7/Y8 cranks are offset drilled instead of straight drilled like just about every other Honda crank. That means one oiling hole per rod journal insted of two.

Y motors are known to chew up rod bearing more so than other older D motors.

MrDelSol253

i just need to know how to prep for a crankshaft installation. how do i clean out the crank case??

TomCat39

You don't. You will very likely spin another bearing.

The D15B7 crankshaft is a single oil hole journal like most of the D series motors.

You can get you mini-me back up and running if you mic out the crank to bore so your bearings are to spec. As well as measure your thrust bearing to be sure it's to spec when you do the new crank.

But as for not getting the knock again, you aren't going to avoid it being the B7 crank really was not designed to rev to the vtec range the mini-me revs to.

It's the same reason why the D16Y8 spins bearings quite often. Single oil holes just doesn't provide enough when you are redlining it.

MrDelSol253

so what youre saying is even if i clean out the crankcase of all FM & install a brand new Crankshaft bearings and all.. im gonna get the knock???

what if i dont redline it? i never redlined much before with the stock d15b7 head....

also what does it mean ti "Mic out the crank to bore"? & can i get that done to my new crank?

MrDelSol253

1.) Will a y8 Cylinder head increase the chance of a spun bearing on the b7 crankshaft?

2.) What is the best head gasket to use?

3.) Do i need to mic out the crank to bore?

TomCat39

It means to use a micrometer and a 0.0001" bore gauge to measure the journals and bores and then ball micrometer the bearings to verify everything is in spec. Plastigauge is only meant to be used to verify you measured everything correctly. It's not accurate enough to be the primary tool to set new bearings.

You can't just slap any bearings into the motor and expect it to work, they have to have a very specific amount of clearance. Clearance in the 10,000ths of an inch range.

If you don't drive the car hard (redline a lot) it will go a longer time without spinning bearings. But the fun of the mini-me is that extra power and rpm... So spun bearings comes with that.

TomCat39

I merged your threads as this is for the same franken motor and quite likely the same car (whatever car that is) this motor is going back into.

Yes, the increased rpm range of the vtec head increases chances of spinning bearings on the bottom end. Even the D16Y8 vtec motor has this issue for the same reason the B7 bottom has the issue with the higher RPM. The issue has already been stated above of the single oil hole per journal.

It's my personal opinion, the best gasket for this build would be the D15B7 Leak Gasket by Ishino. It will provide the perfect .035" quench and squish zones for the flat parts of the head combustion chamber. This perfect quench spacing will help reduce detonation and pre-ignition since the piston goes to -0.002" deck height (almost flush).

You ALWAYS are supposed to measure your journals and crank/rod bores and bearings. The proper method is with micrometers and 10,000th of an inch dial bore gauges. Then verify your measurements with plastigauge as a second set of tests.

MrDelSol253

Well i used a measurement caliper and got the dimensions of the old crankshafts snout, main & rod journal and went up to orielys and bout a matching crank that (supposedly) comes with all the bearings required that are already to spec with the crank itself... if thats true their shouldnt be any problems anytime soon right?

couple more questions... after the two bearings spun it created ALOT of metal shaving in the crank case that got alll in the oil pan and oil sump, i cleaned the pan reallllllyyyy good and let it soak in Hot dish soap water for a few hours to free up some stuborn fm. so my question remains....

whats the best way to clean the oil passage ways in the crank case? is it as simple as spraying some degreaser? i dont want any FM in there to F*** up the crank again, i spent $275 on this new crank from orielys and i really dont have any room for failure. I already spent 230 on a rebuild kit (Gaskets,seals, pistons, bearings, water pump, oil pump and rings)

i just want this **** running right


1.)

TomCat39

The best way is to have the block and head hot tanked.

MrDelSol253

The Block itself is still in the car being supported by the right side engine mount and i have two jack stand supporting the right side of the block, bc i have the tranny taken out right now. I Really dont wanna take the block out just bc i fear i wont be able to put it back in.. this is my first engine tear down that im doing on my own so i wanna make sure i can put this thing back together lolol

would it cause any harm if i sprayed some engine degreaser under the block in the crankcase let it sit for 5 mins and spray some water in there???


btw thanks for the help

TomCat39

I can't say I am intimate with the oil passages on the block. I only just started looking into the routing of oil. You have pulled the pump and pick up tube, so it's now important to pressure flush the paths in the block with oil to push out any metal fragments that might be there. You are supposed to also use a pipe cleaner on various holes to be sure no gunk is built up in them.

The new crank means you don't have to worry about the oil passage through it as it's brand new.

Maybe someone else can pipe in on the best method to be sure your oil passages are free and clear of unwanted material.

Personally I would not use water. The only time water sees a block is when you hone you wash the cylinders with soap and water then immediately dry and oil them.

MrDelSol253

what would it cost me roughly to get the block and head hot tanked