ok. first time doing the rod and main bearings. would i mike the crank in a couple of places to see what bearings to go with? i checked the crank and buffed it up with some emory cloth and put in a new oil pump.crank felt pretty smooth but i would mike it to make sure its not out of round. but really want to know the procedure on finding the correct size bearings. the guy that had it just slapped some undersized bearings and tightned the bolts real tight(no torque) amazingly enough the crank isnt chewed up just a couple of rod bearings. thanks in advance.

 

Yes, use a micrometer on each journal in two or three places and record the diameters. Then, check the original diameter of the journals. (You will need, please, to let us know WHICH engine you are working on.) This will tell you (1) If the crank needs to be turned and (2) what size bearings you must install.

If you will post which engine you are working on, I have several sources so I can get you the journal diameters stock, the spec for clearance, etc. If you wish, I would be glad to get that to you.

Too, if you wish, I can also get you the Clevite part numbers for the bearings the engine requires and the oversizes available from Clevite for it. I am sorry, but Clevite and TRW are the only books I have here listing numbers. Be that as it may, I hope that would be beneficial to you.

 

sorry i did not post the motor type. its a 400 but with a different cam (not stock) and the guy across the road is out of town so i wont know the specs on the cam until tonight. whatever info you can give me will help. chiltons is not very detailed on the use of plastigauge. i assume you uncap a bearing, lay the plastigauge between the bearing and the crank, tighten to torque specs then take the p.g out and find your clearance on the chart. is this correct? thanks for the response

 

Yes the way to find out if the crank needs regrinding is to mike the journals in several places and record the results. Max out of round spec for a 400 is .0006. Main journal diameter on the 400 is 2.9998 +/- .0004. Rod journal dia. is 2.3107 +/- .0004.

As far as Plastiguage goes it's fairly simple. Make sure you buy the green stuff. It comes in different colors for different clearance ranges. You put the upper bearing insert halves in first, then install all the other bearings & caps except the one you're measuring. Don't oil the inserts because the oil will dissolve the Plasitguage. Cut a piece of Plastiguage and lay it on top of the crank then install the insert & cap and torque to spec. Now take the cap off and compare the width of the compressed Plastiguage to the chart on the sleeve it came in. You're looking for a clearance of between .0005 and .0015 on the mains and .0008 to .0015 on the rods.

 

First of all, you are correct in how to use the plastigage BUT, it MUST be used on a clean and dry surface!
On the 400, the crankshaft journal size is 2.9994-3.0002. The size of the bearing housing diameter is 3.1922-3.1930. The clearance for the bearing-to-journal is 0.0005-0.0029. The Clevite part number for the mains is MS981P for engines from 1971-1976; it is MS1432P for 1977-1982.

The rod journal size is 2.3103-2.3111 with a housing diameter of 2.4361-2.4369.
The clearance for bearing to journal for the rods is 0.0005-0.0031. The Clevite part number for the rod bearings is CB927P.

The main set is available in std, ,1, 10, 20, 30 40.
The rod bearings are available in std, 1, 10, 20, 30, 40.

Should your 400 need cam bearings, they are available from Clevite as part number SH510S. They are available in std amd 10.

You might check www.motorhaven.com to see about their pricing on the bearings.

EDIT- MotorHaven does not carry engine parts. -Admin

I hope this helps you out!

 

The FoMoCo shop manual lists .0026 as the max. allowable bearing clearance for both the main & rod bearings. .0008-.0015 is the "Desired" clearance. Now having said that, if you're running a HV oil pump you may want to have your clearances on the upper end of the scale since a HV pump can create excessive back pressure in the system if the bearing clearances are too tight which can lead to failure of the distributor gear.

 

Bill_Beyer is, of course, exactly correct--especially in his advice to go to the high side of the clearance specs IF you are going to run a HV oil pump. Too, to help avoid damage to the distributor gear and oil pump driveshalft, Ford offers a high-stength oil pump driveshaft, part number M-6605-A351 for your 400. They also offer a high-stength distributor gear, part number M-12390-G if you have a cast iron camshaft gear or part number M-12390-H for use with either cast iron or billet steel cam gear teeth.

They are tough parts and, considering the validity of Bill's post, I do feel you should consider them--as well as the rest of Bill's post!

 

man, i really appreciate all this useful info. i was laying on my back unbolting my rod caps and kept looking over at my "a" frame pretty soon i was draining and pulling the radiator, started,p.s etc,etc. started at 8:15 this morning and finally got the motor out 10 min. ago. it was aggrevating because of the 6" lift so instead of taking the wheels off i let the air out of the front tires. im going to go ahead and replace the crank. now that i can look at it in the light its pretty chewed up. new bearings would not have lasted very long.

the guy across the road does not have the specs on the cam he put in, should i just put a stock cam back in? that way i know what i have.

oh and 1 more ?. if i go from 2nd to 3rd i have good take off pretty decent power, but from 3rd to 4th it has no go. now i was there when he adjusted the carb and he just did the adjustment until it quit cutting out. im running 35's with 3:50 gears. would my problem be from

a. bigger tires not compatable to the gear ratio

b. carb running to lean (lean as in no black smoke from running rich)

c.both of the above

carb is a holley 4bbl, dont have a tag on it so i dont know the exact cfm but im going to do a search on carb adjustment and go from there after i get the motor back together. thanks very much for all your input

 

First of all, on your Holley 4-bbl, there will be a number on the upper left hand corner (right hand corner if you stand in front of the engine) that will give a LIST number. For example, it MIGHT read: LIST 0-1850. That is the number to ID the Holley carb. If you can get me that list number, I feel I can get you the CFM and tune-up and adjustment specs for your carb.

I know of no aftermarket camshaft for a 400 that requires a different I.D. or O.D. cam bearings. (I do, however, have some aftermarket camshaft books and I can double-check that for you, if you wish.

In the same train of thought, if you can read a brand name and a casting number off of the front snout of the camshaft, I can also try to ID it for you and get you the perfromance specs for it. If I don't have a spec catalog for it here, I can try the 'Net for you or call a friend of mine who works in a performance engine store in Nashville.
Before you change the camshaft, it might be better to know exactly what you have and what the cam does.
In considering the problem you posted with the drop off in gears, if you please, post what year the vehicle is; what the transmission is--with each gear ratio; if it is a 4X4; and, if it has A/C, PS, PB, etc.

 

ok on the part where the breather slides on there are these #'s 80457-2, then under that on the top of the base is 11761. and thats it other than "holley u.s.a.". the truck is a 78 f-150 4x4, front pumkin reads on the tag 3 50 d9ta 610088-6. rear pumpkin has no tags, but looks factory 9 bolt. running 35.5 x 12.5 x 15 tires.wont know about the cam until i tear into it tomorrow. as far as the crank goes i did not think it was that bad, but its pretty chewed up, and i dont think it can be turned. we have 3 machine shops that i called and can get me a reman. crank with matching bearings. i was going to drop this 88 302 in it which would turn higher rpm's but im afraid it would fall on its face. oh, tranny is a 4 speed granny. thanks very much for the response. hope your around when i start putting the bottom back together. no a.c, have p.s and power booster for the brakes

 

I wouldn't bother putting a crank in it until you get your blocks align bore & rod bore size checked. If there out of spec. it wont last long.

 

Your Holley 80457-2 is a model 4160 4-bbl that flows 600 CFM. The Holley rebuild kit number for it is 37-119. The Trick Kit number for it is 37-912. I hope that helps you out on that part of it.

marka's post about align-boring the block may well be valid. Although, admittedly, the 351M-400 are not quite as prone to core shift as were the FE and FT blocks. Still, the way you describe the crank, I feel I would surely have it checked at the very least and probably align-honed.

Since you posted more of the particulars about your truck, I will see what some cam catalogs call for. I will post that as soon as I can.

Before I forget to ask: Does your truck have factory exhaust manifolds or headers? Is it single or dual exhaust, please?

Finally, at what RPM range will you operate the truck MOST? What will be your highest sustained RPM? How will you use the truck the MOST? No, this isn't trying to be nosy nor intrusive; much rather, picking a cam that works is dependent, in part, upon knowing these factors.

 

thanks for the info on the carb. ill search for the adjustments for it tonight. the truck had just the factory headers and i ran my own exhaust(dual) with cheap mufflers just so i could listen to the bearing noise. what are the pros/cons to running a stock 302 with the lift setup and gearing that i have. i have the motor mounts for the motor, clutch plate, clutch, and flywheel out of my 70 1/2 falcon. plus the bellhousing. i have a 4bbl tarantula intake that will bolt right on and the manifolds. if its not worth the bother, my truck will be down for 2 weeks. if i can get by with it and do the 400 re-build, while i run on the 302, then i can be in my truck by the weekend. let me know and thanks.

 

The 302 should, I think, move the 3.50's fairly well. Ford used them in LTD's with fairly high gearing, as a matter of fact. I am going by memory here, so that may be dangerous...but, I do believe the engine stands upon which the mounts bolt are different for the 302 and the 400. Of course, the mounts are totally different--the 351M and the 400 had mounts different from ALL other Ford V8's. However, due to the differing width of the engines, I do believe you would need stands for the mounts for a 302.

The lift kit itself is of no consquence; the bigger tires, however, have the effect of giving you a higher gear (lower numerical). I would have to put a calculator to that one to figure it out; I can't do the math in my head.

I am looking at a couple of catalogs for cams for you now. I will post what I find ASAP.

I did not find exact tune-up specs for the carb. I am sorry about that. I can look more for you if you wish for me to do so.

 

From Ford Motor Company, I would suggest the M-6250-A341 cam. It has good torque with stock rocker arm ratios. It is 292 degrees of duration on the intake side and 302 degrees of duration on the exhaust side--very important for a Ford engine. Ford recommends it for good low- to mid-range torque and HP and a fair idle. It is recommended for a stock or mildly modified engine. It will work with your 3.50 gears and your manual transmission and will work better with no A/c.