360 Damper Install

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JRapley

JRapley

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May seem like a simple question, but I'd rather get it right the first time instead of having the pull something apart after assembling it incorrectly.

Installing my stock 360 damper onto the crank end, is there any sort of sealant used? Does the press fit between the damper bore and crank provide a good enough seal to prevent oil from seeping out between the machined surfaces?

Only reason I ask is my maintenance manual states nothing about it, but when I pulled the damper off the old engine there was a pink 'paint' on the end of the crank. Wondered if this was on there for a 'sealing' purpose, or just assembly markings.

Thanks!
 
I always used i bit of oil on the surfaces just to help it along. Outside of that everything else should be straight forward. There a rubber seal on the water pump housing that keeps oil from coming out.

jake
 
Leave the timing cover bolts loose when you install the dampner so that the dampner centers the cover seal on itself. Then tighten the cover bolts up once the dampner is on all the way. The cover has a little slop in the bolt holes and will move around a bit. Neat little trick I learned in a Mopar engine rebuild book when I did my motor this fall.
 
I spread a small amount of RTV in the keyway before installing the balancer.
 
I agree with previous posts. Personally, I use anti sieze on damper bore. But before I install damper, I match mark the outer ring and the inner flange to check later if there is a question of the outer ring slipping.
 
Always use antisieze on the crank. It's a press fit. Well, it should be.


Also, I always measure the press fit. If it has .0012-.0018 it's good to go. Any more than .002 is pushing it. Less than above its either the crank is undersize (seen that with some China stuff) or the bore in the damper is blown out.
 
Thanks for all the information guys, I really appreciate it. I'll grab some measurements from the crank end and damper bore and just check the fit will be within range. The damper did seem to come off the old engine pretty easily with the puller, but then again, it was soaked in oil due to the front oil pan seal leaking like a sieve.

I guess while we're on the subject of the front end assembly, does anyone recommend using anything other than the paper gasket for the timing cover install? I was thinking of using a small film of RTV on either side of the gasket to keep it in place and aid in sealing up the timing cover to the block. Especially since I'll be juggling around getting the accessory brackets & water pump installed, which share the same through bolts.

Thanks again
 
I always use the Ultra Grey permatex on all that stuff. I've seen so many of these older aluminum water pump housings and timing covers that aren't exactly perfectly flat and smooth after years of coolant and use. The permatex goes in between the little imperfections and takes care of that plus it gives it a better seal.

Oh and make sure you get a decent amount in the corners where the oil pan and timing cover come together. it loves to weep outta the corner where the gasket for the oil pan and the cover meet.
 
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66d806a5-a886-4c23-a7f2-fd989b2048dc
Here the stuff I use. It doesn't harden and it seals good. Can be taken back apart and you can reuse your gasket again. I liked it so much, I took a picture of it, so I wouldn't forget. Permashield

upload_2016-12-24_11-5-34.png
 
66d806a5-a886-4c23-a7f2-fd989b2048dc
Here's the stuff I use. It doesn't harden and it seals good. Can be taken back apart and you can reuse your gasket again. I liked it so much, I took a picture of it, so I wouldn't forget. Permashield made by permatex.
93420eb4-a3dc-4099-bc53-c12e297b1dba


upload_2016-12-24_11-12-14.png
 
for the bolts which go into water jackets (all the one which aren't blind holes) , I coat the threads with Permatex #2 (?). It's the brown gooey, messy stuff in a short little plastic bottle with a brush applicator attached to the lid. You put it on the threads of the "wet" bolts to seal the water jacket bolts. It's good because it doesn't harden and if you have to loosen bolts for any reason, you don't have to pull bolts, clean the threads and reseal them. Personally, I use dry, dummy bolts for the water jacket bolts, first, until gasket cement has cured on timing cover, so the gooey thread sealer doesn't contaminate the fresh uncured gasket sealer when first assembling. Then you can replace the dry bolts with the final wet bolts, one at a time, in a less hurried, less messy fashion.
 
Long time ago, I did the front with all-thread...because I had misplaced all the special length bolts! RTV'd the ends of the wet threads, mounted and cut flush when it was all buttoned up. worked suprisingly well. They dont hold a torque, but nothing up there is torqued past 35 anyway. They stayed in the block when I pulled the front off and saved the weak AL threads from water pump bolts. Only downfall was it made it necessary to pull the radiator for any front work becasue the case had to be pulled off way past the studs.
 
Thanks again everyone for all the great info! I ended up putting it together tonight and all went well, but I guess the proof is when I get the engine off the stand and running in the truck.

Unfortunately I wasn't able to get the oil pan on though. Realized after putting the new oil pump in place that I had no bolts for the pump itself! Ah well, off to the store tomorrow to get a couple!
 
you can pack your oil pump gears with vaseline if you want the pump to prime instantly. The vaseline will stay in the pump until you crank it, prime instantly, and then dissolves into the oil quickly.
 
Be sure that the bolt on the snout of the crank for the damper is fully torqued to spec, especially if you put any sort of oil or anti-seize on the crank snout to make installing easier. And use the thick washer that comes under that bolt. The system depends on this bolt and thick, hard washer, plus the high torque on the bolt, to lock the damper hard to the crank. And make sure the damper fully seats in so that the inner end of the damper is fully and firmly against the shoulder on the crank.
 
@nm9stheham, I ran it up with a ratchet and then torqued it up to 135 ft/lbs. Re-used both the bolt and thick washer that came off the old engine. Cleaned them both really well to ensure clean threads with little resistance. To me it looks to be seated fully, especially due to the fact that if it went on much further it would hit the timing cover where all the timing marks are.

@rustycowll69, Another good heads up about packing the pump, never would have thought of that to be honest. I planned on getting a piece of hex stock and turning the pump with a drill to make sure oil was getting to the top end with the valve covers off.
 
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Unfortunately, posts show up every now and then about loose dampers and damaged parts. The damper has to be hard locked to the crank to do its job (which is to damp out internal crank vibrations that have nothing to do with engine balance BTW). The key is only an alignment guide; the damper depends on the clamping force of the crank bolt to essentially become part of the crankshaft, and that is why the the torque on that bolt is so high.
 
if you're going to do that, screw a mech oil pressure gauge in, and make sure you have good oil pressure, as well as watching for oil at the rockers. Don't know if this is a magnum or LA motor, if LA make SURE rocker shafts are oriented correctly.
 
It's an LA block (1972) with a set of magnum EQ heads. The machine work and assembly (including heads) was done by a reputable shop. I'm just finishing the build up myself as I wanted the experience. So I'm in the midst of putting on oil pump & pan, timing cover, water pump, accessories, intake, valve covers etc etc. This is my first go round at this sort of engine build up, which is why most of the questions may seem simple, but I'd rather get it right than mess something up. All the help is much appreciated.

Here's a couple pics of where the damper is sitting. Unfortunately looking in from the bottom side the timing chain is in the way and I cannot see if the damper is fully butted up against the crank or not. It was definitely hard to get it torqued
to 135ft/lbs, so I'm thinking it's seated fully.

IMG_3337.JPG


IMG_3338.JPG
 
it's kinda hard to see, you can tell best of all, but if it looks like it can't go any further or it would be rubbing on the timing cover, you should be fine. Try using some white-out on the timing mark on the damper outer ring. The reason I caution you about rocker shafts orientation, is because if the oiling holes aren't locating correctly, you could seriously damage all the bearings, crank, oil pump, rockers shafts, etc. Bad news all around.
 
That's seated. It can't go on any further.

BTW, I never use anything in the oil pump. I just take the cover off, use some assembly lube on the rotor and scroll and put it back together. Don't use cam lube, use engine assembly lube.

I've never seen vasoline or anything else make the engine prime faster. Even if you do the vasoline thing you still need to prime the system by hand before firing it off.

Make sure the total timing is at 40 degrees or more, up to about 50. Don't time it at zero. Once you get a few minutes on it, you can pull it back to 38 or so if you're uncomfortable. Slow timing will stick exhaust valves and make it hard to start.
 
ok, re-read previews post. not familiar with those heads, but if they are later year magnum style heads, disregard comments about rocker shafts, because that's a different situation entirely.
 
Lookin' good OP. If it drew down on the crank snout and reached a point where it suddenly started torquing hard, then it sounds like it seated well.

Not sure why vaseline wouldn't help priming, especially with a used pump. OF course, gobs of engines have been started and run with no priming of any types, and lasted just fine, including racing engines. (Some cannot be primed except by a pressurised oil source.) Priming at least helps spot some common errors... like oil gallery plugs left out, and feeling for the turning resistance to increase when the pressure comes up.
 
I'll be using a brand new oil pump. Figured for the price of a new one being so inexpensive compared to the rest of the build, it's cheap insurance to have a new piece.

My next question is regarding the intake. The magnum EQ heads have coolant passages on the front and back of the heads, I'll be using an Edelbrock rpm airgap (7576). Now this intake doesn't have any rear coolant passages to match up with the ones on the heads, basically it blocks them off. Does anyone have experience with this? Any issues with blocking off these passages? I can snap some pics if needed to show what I mean.

Thanks again guys for all the help and insight, helps a bunch!
 
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