last week i started opening the motor to change the camshaft and after seeing how dirty the valves were i decided to take the engine out and check the whole thing.
i just finished measuring the main bearings with the plastigauge and reads like this:0.004 and the manual says :desired 0.0010-0.0015
the old bearings read 0.010 so may question is what size bearings do i need to reach to the desired 0.0010?
i will probably buy from summit and they sell:stock .010-.020-.030-.040 and .001
the rods to crank read 0.002-0.003 and shop manual says:desired 0.0010-0.0015
thanks in advance and any suggestion would be appreciated.

 

You likely have to have cranked turned to .020 under and get new bearings.

The old bearings are already .010 under, and it's slightly worn, so not much you can do with it.

Performance builds usually go between .002-.003 on clearances(depending on opinion), then usually a HV pump. I would not rely on plasticgage to determine accurate clearances. In a pinch maybe to re-confirm what already know.

What is the overall use of motor? plain stock rebuild? Hipo rebuild? That will determine what it needs. The rods are just about fine, the crank is a bit loose. Turn the mains, leave the rods alone is an option. I would get the journals measured with micrometer to better asses the wear.

 

Excellent advice...I like .0025-.003 on the mains, just as Freightrain has suggested.

 

hi thanks for the quick response freightrain! the motor is for my 72 f250 4x4.it already has an edelbrock performer rpm intake,speed demon 750 carb and headers.so based on that im thinking on a comp cams xe 274h-10 cam(Duration at 050 inch Lift:230 int./236 exh.) ,new lifters,springs.
im just trying to minimize the machine shop part,not only because of money but quality too,here on maui theres not many shops to choose from.thanks!

 

Those tight clearances are fine for a grocery getter stocker, but if you plan on running it harder, you won't get the oil it needs. In a pinch, I'd run the rods like they are, get the mains turned and get .020 bearings for it.

This is where having a reputable shop or micrometers come in handy. Torquing the rods/mains, measuring the bores, comparing bearing shells and determining your TRUE oil clearance. If you can't do that, then have them turn the crank to low side and hope your bearing shells are nominal and this will get you the added clearance you need to get .0025-.003. It's not rocket science, but the better you set it up, the better it will be.

Might even just order a new set of bearings, and recheck your clearances. The fact might be the bearings were slightly worn too and if you polish the crank and use new bearings, it might tighten the mains up? It's not terrible, but .004 is kinda loose and you'll likely have low oil pressure. A HV pump might help that issue too.

I take a HV pump and shim the spring .100 and it bumps the pressure up. Gets me 60+ psi running down the road and 80+ at 6000 rpm. I'm kinda partial to higher pressure, though some say it's a waste of power. If you shim the spring, you'll need to make a plate to bolt between pump and pickup to hold the cover on. Simple to do with hand tools. These days, I make a pipe plug and machine it so it threads in a specific depth to get my .100.

Do you plan on doing any oil galley mods? Anything will help.

 

"and hope your bearing shells are nominal " does this mean that where the bearings sit could be bigger than stock?
am i gonna be able to reach the "desired" 0.0010 -0.0015 by taking the crank to a machine shop and using the .020 bearings?if so do the machine shop need the new bearings to see what to do?
before opening the motor i had 45psi when cold and 25psi when hot.
i will put a hv oil pump,i have no idea what inside one but i took note on how you shim it.is there any way to regulate the pressure?and is it a good idea or no need?
and whats the oil galley mod?
thanks!

 

Yes they need the new main bearings and the crank to check with a micrometer for the proper clearance of .025- .030
Oil galley modifications are very important if you are going to run higher rpms. Do a search on this site for the modifications. I modify all my FE oil galleys. As to high oil pressure, some like it and some don't. I like using the Melling M57HV (high volume) pump with no modifications. Some people blue print the pump.
fyi ,,, how they check the main bearing clearance is to install the new bearings in the block, and check the inside diameter, then measure the crankshaft. You want a difference "clearance" of .025-030

For the oiling modifications, put an old set of main bearings in the block, and look at the mismatch of the oil holes in the bearings to the oil holes in the block. I use a thin marker to mark the hole of the bearings over the block holes. I then grind out the mismatch. I do this before hot tanking the block, and thorough cleaning. Also gradually drill out the oil hole from the oil filter to the oil pump and finish with a 7/16 drill bit. Also enlarge the oil opening "in the block" to the oil pump to match the gasket. Chamfer the edges.
Some may do it differently, but I have never lost an engine due to oiling problems.

 

ok i just ordered the .020 rod and main bearings from summit so next week i take the block to the machine shop.what about the cilinders?i check them and i can see the cross diagonal marcs from the previous honeing?and i measure 4.079-4.080 with a digital caliper.can i just hone them again with the drill and put new gapless rings or would they need to be machine to the next size?

 

Maxtor covered it pretty well. Yes, within manufacturing specs, the thickness of the bearing will differ "slightly". When building mine, we'll got thru a couple sets and try to match up a set. Now that's cutting it pretty fine, but when "blueprinting" a motor that is what happens. The sattles of the block that the bearings sit also could be out of round or varied in size. It all makes getting clearances a real chore.

To get exact numbers, you need to install the bearings in the block, torque it all down and measure the bores, compare to crank journal diameters and the difference is the clearance. Without doing that, it's all a moot point to get critical. Doing the bearings FIRST, allows you to tell the machine shop to maybe grind the crank to the LOW side to get more clearance, understand? Since you can't buy a varied assortment of bearings for FE motors, you have to adjust things. Chevys offer .0005 over/under bearings that you can use to make/remove clearances and not have to machine anything.

If you're just going with a std rebuild, then just allow them to finish it to "stock specs". We're really throwing alot at you with all this, but we're trying to get the best build for the money. Can you ask the shop to build it to "your spec" (looser clearances?)

You need to run a bore gage thru the length of the bores to see if there is any taper. Measuring the top will get you an idea, but if there is alot of taper, then you need to bore it. Again, have the machine shop measure them for you, and then you can decide.

Do you have one of the FE rebuild books for reference? Might be a good idea so you can go in with information to give them.

 

while i wait for some parts i want to start disassembling the heads and i need a good valve spring compressor and dont know which one to buy. anyone has a good one to recommend?also how can i clean the valves from all that black staff without scratching them?

 

heres an update on the rebuilt.i got a spring compressor from sears that works really good and cost me $22.now i cleaned the valves pretty good but they look worn on the stem ,where the rubber seal rubs.
then while flipping the super heavy head i heard something loose inside.there was a piece of rusted metal in the water passage ,a piece of 1/8 rod about one inch long welded to some rusted out sheet metal.i manage to take out the rod part and the other part is still inside.is there something i can do or the machine shop can do to clean the water passages from all that rust?

 

Before you do a rebuild, everything needs to be squeaky clean. The block, heads, intake, tin, etc. all need to be cleaned in a "hot tank" at a machine shop. They should have special brushes to clean the oil passages, and all areas of the engine. They will knock out all the oil plugs, and replace the plugs when the engine is clean. If you ignore this step, you are begging for an engine failure.

 

Pro Form has a good HD valve spring compressor in the Jegs catalog pn#778-66832 $95.99 .It`s about 1,ooo,ooo times better then Sears

 

I have/had the Sears version. Perfect for very, very stock type springs. Anything better and it folds like an accordian(ya, I know from experience). Still laying around under the bench somewhere, not sure why?

 

second update.i bought the "how to rebuild BIG BLOCK FORD ENGINE"(FE-FT),great book,thanks for the tip freigtrain!still didnt find a quality machine shop.the most impressive one doesnt even have a hot tank.i could take the block to oahu with the superferry but it they shut it down.
on the good side,i put new .010 bearings and got .002 of clearence,thanks freigtrain again for the tip!
i bought all kind of tools like the cam bearing removal/install.,bore gages,micrometers,etc.i clean the block 3 times already,remove the freeze plugs.if it wasnt for the wd-40 i said i could lick it.
next i gonna do the Maxtor oil modification to the mains holes.
while looking for parts i came across these ,tell me what you guys think,
aloha and thank you!

eBay Motors: Ford FE Deluxe Main Girdle 352 360 390 406 410 427 428 (item 260402759032 end time May-07-09 14:48:20 PDT)

eBay Motors: FORD FE Shaft Mount Rocker Arm System 1.75 Ratio (item 120415013844 end time May-09-09 15:33:38 PDT)