spent saturday putting my 75 225 back together. a few questions came up:

1) can I use white lubriplate on the cam lobes? I have been told by some it is the same as cam lube, and by others it is a bad idea.

2) my FSM in the beginning says the torque specs for a 7/16 20 grade 8 bolt is 70 pounds. when reading the instructions for replacing the rear main oil seal, it said to torque the rear main cap to 85 pounds. which is right?

3) how freely will a new assembly with all of the pistons, rings, rods, and crank assembled turn by hand? mine won't move at all without a huge amount of effort. I had the block bored .060 and line-honed, the crank is within .001 true. all components were balanced (individually and rotating together).

any help is appreciated.

1. I wouldn't use the lubriplate on the cam and lifters. Go buy a little packet or bottle of cam lube from a good parts store or speed shop.

2. There is a table of engine torque specs. Use that table not the general fastener table. This is critical!

3. Once the pistons and rods are installed there will be a lot of drag. Most all of the drag will be from the rings. If the crank is in the block by itself with the main bearings torqued it should spin easily. It sounds as though you have a problem. Pull it back apart and see what's wrong.

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Joshua

joshie, I tried looking around in my area for a decent shop that would sell cam goo, but couldn't find one. I am still looking around. I just was wondering if the lubriplate is a good substitute.

and the crank did spin quite freely when I just had the mains on and tightened. it didn't get hard until the pistons were installed, I was just asking if that was normal because I wasn't familiar with how much drag is normally present, I should have mentioned that in the first post.

Find a place that grinds cams and they will have the proper lube. Search summitracing.com for cam lube and you'll see what you're after.

Ok, put a bolt in the front of the crank and tell me how many ft/lbs is takes to spin the engine. We need to better quantify this "huge" effort.

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Joshua

Any speed shop should have cam break-in lube. Mopar Performance also sells it. A bottle of GM EOS is a good idea during break-in too.

Does the motor spin freely after initial break-away? My first motor took a lot of torque to break it loose, but spun very freely after that. It ran for years.

Assembly lube and bearing clearances also make a difference in break-away. Motors assembled with oil will spin more freely than ones assembled with white grease.

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Official Cookie and Mater Tormentor.

Since this began whan you installed the pistons I would make sure the rods and caps are still mated to each other the way thet came apart. One way to check this if they were stamped with corresponding numbers. If not, use your FSM and some plastigauge to check the clearance between your bearings and journals. Also you should measure your bores and piston diameter and ring end clearences.
All new motors are difficult to turn by hand. Without trying it in person I couldn't tell you if it is just a new engine or if you do have a machining or assembly problem. If you do have doubts, I would check the above dimensions.
Hope this helps,
AZ

Having the spark plugs installed makes it WAY harder to turn than without plugs in, too. You're fighting engine compression when the plugs are in and the chambers are sealed up. When I'm doing this kind of thing, I do a rotation test after each step. First the crank in the mains- spins good? OK. Then first piston and rod- a little harder (no head installed yet). It should start feeling fairly stiff when all the pistons are in, but with the head(s) off it shouldn't be a "heave and grunt" kind of thing. Then put the head on with all the valve gear but no spark plugs- that will be the total mechanical resistance of the engine and it can be surprisingly stiff. But when you put the plugs in you can no longer separate the mechanical drag from the compression.

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head isn't on yet-

I know the rods (all rebalanced and striaghtend) and clearances are good, I will check when I get home with a torque wrench what the amount is to get it to turn.

If you get a rod or a main cap 'reversed', the engine will be hard to turn. Rod and main caps only go on one way, the way they were assembled when machined. The bearing insert 'tabs' will be on the same side and with the con rods, there should be stamped numbers that will both be on the same side. Double check everything, keep asking questions, make sure it's right before installing and starting.
DD

My 225 was hard to turn when rebuilt and that concerned me too. With no crank bolt, I used a vise grip on the balancer with a pipe over the vise grip. It was still hard to turn without spark plugs in. 1500 miles later, it seems to be fine.

I didn't get a chance to put the torque wrench on it last night, had to take the boy to cub scouts and fix the daily driver. the more I think about it and talk to others I see this may just be normal tension caused by drag of a new set of pistons and rings.
thanks for your reply. I was aware that there is a certain way the caps to go on, and I was there when the block was line honed so I am sure they were put back in the correct spot, along with the correct lining of the oiling holes (being on the same side, meaning rod hole to rod cap hole). this is also what the picture in my FSM shows. all this combined is making me think it is normal to have this drag, but I do still have a question:

lubriplate and cam goo. I know I should continue to look for cam lube (once I finally find a shop that sells it in minnesota) but what I had been told earlier was that you should never get the cam lube (being a different type of goo) on the bearings because it will do harm. this I am having a hard time beleiving since it is all in the crankcase anyway, and will eventually be sloshed around through everything else. this makes me think the explanation is bogus. I am not saying they are the same thing (cam and lubriplate), I am saying I don't think it is really going to harm it.

am I wrong?

Cam lobes and lifters are made of iron. Main and rod bearings are made of steel lined with either aluminum or copper and babbit. There are chemicals that will attack bearings that won't attack iron or steel. Whether or not the cam lube has any of these chemicals is questionable. Once the engine is started and the cam is broken in you should be changing the oil anyway. Chrysler recommends this with their cam lube as they don't want it in the crankcase long term.

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Joshua

Cam lube will not hurt bearings by contact. It is just too thick for the tight clearances and can clog things up causing extra friction and prevent oil from flowing. Besides, you just don't need an extreme pressure lube in the bearings. When cam lube has been used you need to change the oil within a half hour or so of running time because the moly will have clogged the oil filter. This is a bigger deal on race engines that do not have a filter bypass.

It "should" not hurt anything, I have used cam lube on the bearings before. But I alsways change the oil after 30 minutes breakin time(long enough to get the cam seated) before any test driving.


On your engine being to tight or not, I agree with what was ask before. How much is hugh, the torque wrench reading would say alot. But you said the crank spun freely with out the rods & pistons, can you move each rod side to side on the crank now after they are install. Atleast you would know if the drag was from the pistons or you could have a rod that is to tight. If the rods will move side to side freely then I would guess it being OK. Let me ask this, was rods & mains plastigauged. Do you know how much oil clearance you have.


Jess

okay, so I was potentially wrong, it can possibly hurt the bearings if left in longer than the usuall first break in period ( I heard 20 minutes at 2000 rpm?) and it is a much thicker goo than the lubriplate.

I'll try to get out the torque wrench tonight. I used the clicker to assemble it, but I'll try an older beam type to measure the crank torque because I don't want to hurt the new clicker. damn things are pricey.