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Part One Just got my cam from the jest coast. Crower gave some pretty good background on cam install and degree-ing. Also a tube of cam lube. I don't think I'm gonna degree the cam unless one of you freaks out and tells me it's imperative in the 258. I will in the 455, but enough of that here. The lifters seem like quality units. They smelled like kerosene. I wonder how many manufacturers of lifters there are? Seems to me like you could make them on a CNC lathe... I was going to use Rhodes lifters, but after a long convo. with the tech. guy at Crower I decided to go with theirs. Why? Because I already knew that the Rhodes "click" from Buick applications, but there it's a beautiful sound and actually helps smooth the idle and torque characteristics and vacuum. (It's not the same "click" as our beloved 360s) In the 258 with the "torque" cam I was not convinced that they would be right, and the Crower lifters were a no-brainer, required no re-disassembly, are supposed to be a quality bleed-down lifter (as opposed to the variable lift associated with the Rhodes), and I didn't want to "un-do" the advantages I may get with the new cam. Plus the price was right. They gave me jobber price on the cam/lifter set. I believe this was because of the lobe separation/overlap questions I was asking-he may have thought I was a shop or something. Anyway, the Crower "Baja Beast" (no pretension here, eh?) cam comes on @ 1K rpm which is essentially off idle to 5K rpm. I'm not looking at the spec. sheet right now but as I remember it has 280 dur. and .448 lift which I compared to the 79 factory specs- I THINK the stock cam has 243 dur. and I can't remember the lift, but it was a lot more. (real specific, huh...) I also went with Crower because my past experiences with the "big" guys (Crane for one) is that they don't put a lot of actual research into the "off" brand engines-merely putting say a Chevy big block grind on a Buick 455 cam billet. WRONG WRONG WRONG!! I suspect that some 258 cams are a 292 Chevy on a 258 billet. Any comments on this? Different flow characteristics in different heads require different overlap/lobe centers. Crower SEEMED to have gotten this down, but we will see won't we? Also the guy took time with me and didn't seem like "Oh great here is another wing-nut who is gonna waste my time and buy a Crane cam". I will be using a Lunati cam in the 455. E-mail me privately for info on the 455 progress. Part Deux Didn't decide on a gasket set yet. I may end up buying an engine set for the general stuff and buying a separate front seal, rear seal, and head gasket that I feel are quality units. Why? Because the thing is on a stand in my comfy basement. Ahm really gonna hate it if anything leaks after it's in Mr. Beef. Well actually I'm kind of projecting-the 258 is still on a dolly on the floor, but I'm slowly getting the accessories off... This may amuse some of you: progress was slowed by the fact that I tried to take off the flex-plate in the bed of Mr. Beef so's I wouldn't bend it or that cover plate behind it while unloading it. WOW! Are those things tight or what?! I took a 1/2" breaker bar and a 3' cast-iron pipe to crack 'em loose. Well one of them was extremely obnoxious and I broke my socket. Well. Mr. Cast-Iron extensions met Mr. Finger who was resting on Mr. Beef's bed rail probably at around 100 ft lbs. Mr. Finger really hated that and is going to lose Mr. Fingernail sooner or later... Anyway I'm gonna pick up some AMC blue paint and some black high temp for the exhaust when I get the seals. That's it for now, will check back in on Monday-hopefully with the cam install report. Part Three Well 258 fans- Didn't get as far as I would've liked on the 6 this weekend, because I eyeballed the mounts on my motor stand and went to the hardware store to get grade 8 bolts to hold up the 258. Well Murphy showed up and of course I didn't get them long enough-of course a discovery I made AFTER the store was closed. RAGGUM! FRAGGUM! SNERTZ! Sifted through my 5 gal. juice bucket of bolts and came up with the right ones anyway. The bare block is sitting on the stand now and I have 1/2 of the lifters out. I used a dental pick to fish the lifters out of the block. I also found the oil change records out of the donor Cherokee. They changed it every 3k like clockwork, and boy does it show! I can still see cross-hatching on the cylinder walls and the top of the heads looks real clean with very little scunge. The fresh oil I drained out smelled a bit like gas which I attribute to the fact that the vehicle was probably always driven with the choke on (short little hops, never got to warm up). It took 6 years for them to rack up 3k miles according to the records!! You may remember I posted a question about this steel vac. line that ran from the intake to the exhaust(?!) Yeah, I thought it was weird too, but I found when I took off the manifolds that for some strange reason wherever that thing went, they disconnected it and put it in the hole in the rear of the heat riser(?!) Go figure. Where DID the steel vac. line go that was tapped off of the rear of the intake? Anyone? I have a question about the CTO and EGR switches. The CTO uses manifold vac. until it warms up then it is drawn from ported vac. on the carb. This seems like an emissions thing and would probably be better to just always run the dist. adv. off of the manifold for max. advance. Anyone? Same question for the EGR. Could I just bypass the switch and always run the EGR, or is it better to have that used only when warmed up? FINALLY! Got the balancer, fuel pump, lifters and cam out of the block today. Most of the lifters came out the other day, but some of them were stubborn. I went to my buddy's garage to borrow a lifter puller, but he said they break more pullers than he cares to say. They told me to just use lots of WD40 and work 'em out. He was right. It dissolved the varnish on the bottoms and out they came! I have decided to use a new timing chain since I'm in there, also because it is the bogus stock nylon type. (What possessed them to do that?) After looking around for awhile I decided on a Fel-Pro set of gaskets which come with rubber seals (as opposed to rope timing, etc) I'm not sure yet if the set comes with a rear seal. Do any of you have any input on whether or not to use any sealant along with the head gasket? I know of a couple of machinists who all say plain gaskets are usually the best in most situations. When I'm in doubt I usually use the thin Permatex in a can with a brush. (but have never used that stuff on a head) Very seldom do I use the thick shmootz in a tube, even on supposedly leaky Harley projects. (I find most Harley leaks are owner-inflicted) Anyway tomorrow I'll loosen the main caps and replace the rear seal and take the wire wheel to the oil pan and loosen the scale to get ready for paint. I'm gonna clean the lifter galley a bit and then I'll put in the cam and lifters. Then on with the pan, timing cover, etc. It's beginning to look a lot like xmas... Part Four and a Half Today I picked up the all-steel timing gear for the 258. It's a beautiful thing. The one thing that I noticed is that on both the nylon AND the steel, there is no provision for a bushing for the cam which means that there is no way to degree the cam in the 258??? I find this hard to believe. Maybe one must buy a special gear. Well folks that ain't happenin'. I have faith that the steel gear will be accurate and consistent enough. Let's keep in mind that stock motors run for MUCHO miles and don't come apart (unless Brad is beating them) granted, not with the performance I expect here, but the point is that I'm not going to lengths to degree this motor. If it all were right in front of me I'd do it, but it aint. Well it would seem that I'm done playing scrape master, so tomorrow looks to be the day the put-back gets under way. So far the costs have been:
Didn't list the Jacobs 'cause that will be used on that OTHER motor, but if you want to add the cost of it to see what my performance cost in the end add $238. I s'pose you could also add an exhaust. Hmm... dis AM spensive! Well actually $400 without the Jacobs isn't TOO bad for what I'm getting. I'll update you tomorrow on the progress. Mon, 10 Mar 97 Hi guys- Today I was checking out the IFSJA site and noticed that Doc paid me the complement of putting these 258 series posts in the Tech area. (editor's note: Hey, no problem... excellent article you're doing, here, keep it up! - Doc) Many thanks to you Doc! Because of this, I would like to start this next post by outlining a few parameters for this project, as I will make the assumption that some of you are following this mess, and Doc will continue to update the site. (editor's note: ya better kronkin' believe it! <grin>) First and foremost, I am not an expert on the 258, or any other engine for that matter. I do however have a fair amount of hands-on experience with different flavors of GM muscle car and Harley engines. This is more of a group "learn-from-my-mistakes" type of thing, and anyone who would like to challenge my methodology or motives is more than welcome. I reserve the right to change my mind as better information and options become available to me. Secondly, this is not supposed to be a max-effort stompin' 258. My goals are to have a tight, reliable, well mannered engine that will start in the coldest weather. Keep in mind that I am located in the great NorthEast and as such am subject to brutally cold wind chills from time to time. I will sacrifice some performance for reliability, as this engine is going in an all purpose used-for-real type J series pickup-Mr. Beef. I am beginning to assemble the 258, and thus far have run into few potential problems. I started the reassembly by removing the rear main bearing cap and replacing the rear main seal. It helps to loosen all the bearing caps and lightly lift up on the crank to get the upper seal slipped around. Otherwise the block starts "shaving" the seal on the outer side of the seal. BTW-I followed the shop manual to the letter on the rear main seal install-went great. I then re-torqued all of the bearing caps and connecting rods to the factory in-service specs. I then took the cover off of the oil pump and inspected the gears-looked great with normal wear marks. I forced some break-in supplement into the pump and up into the block, so the pump forces that through everything first. I them coated all the contact and wear areas with break-in lube and reassembled the cover gasket with a light coating of Hi-Tack and torqued all oil-pump related fasteners. BTW- at this point I began playing with the pan seals and although not specifically addressed in the manual, it looks like the proper order of assembly with re. to the seals is as follows: inner rear main bearing cap (lower) seal flush with block/cork pan seal tabs set on top of lower seal tabs/outer rear main cap to pan seal set on top of cork tabs. It looks like RTV at the junctions just mentioned would be the way to go, with Hi-Tack brushed on to the cork gaskets prior to placing them on the block. Any input on any of this you guys? Anyway I'm getting ahead of myself-just fitting the gaskets and making a plan. I'm going to insert the cam next time with the pan off in order to support it while threading it through the block so's I don't nick the bearings or cam. This is of course provided that I actually USE my cam-there are some 11th hour reasons to doubt it's effectiveness. Date: Tue, 11 Mar 97 23:53:23 EST OK! The project is starting to come together as I am getting into the reassembly. I forgot to mention last time that before I put the oil pump cover on, I packed the pump with Vaseline. Also on the subject of replacing the pan gasket I should have gone one step further and said that the point is I feel it would be better to get the rubber seal that rides in the bearing cap groove as well as the cork gaskets when doing a pan-drop type repair. Anyway-in the interests of cleanliness I had already cleaned what little sludge and deposits there were in the hiding spots in the block. I have also torqued all lower end connectors/cleaned gasket surfaces/etc. While the block was flipped upside down I cleaned the cam bearings and coated them with assembly lube, coated the cam with the same and installed the cam making sure not to nick it. While upside down you can support the cam while threading it through the block. At this point I prepped the oil pan by scraping the sludge out and running it on the wire wheel in preparation for the coat of AMC blue. I installed the gaskets, evenly torqued the pan down and flipped it over in order to install the lifters. In case it hasn't occurred to you, don't flip the block over with the new lifters in it-they don't have varnish on them and will probably fall out and you will hate that. I soaked my lifters overnight in break-in lube (there are many schools of thought on lifter prep) , wiped them off and coated them in assembly lube. They slip right in no problem. Hmmm! Excitement is growing as it am lookin' like this thing might just run again. I'm going to stop here so I can get this out, the next post will be on the head prep and valve seals/de-coking (as the Brits say) et al. In the meantime it's on to the dreaded wire wheel to clean up all of the remaining fasteners in order to prepare for the final stages of assembly. That's all for now- Brad Feick Date: Mon, 31 Mar 97 22:30:53 EST OK! After emerging victorious as the winner of discontent with Dr. Jacobs crack sales dept, I am ready to get down to some serious bidness with the 258. There was recently an FSJ How-To on valve seal replacement done by_________ which can be viewed on the IFSJA web site. Because of this I will not duplicate______'s fine effort here. I will however add that I used a K-D claw-style spring compressor, and I did the valves with the head removed and had no problems. One advantage to replacing valve seals with the head off is that you can lap the valves ( warning-they don't taste very good) and de-gunk the chamber while you're at it. I carefully wire wheeled the deposits off of the valves and buffed them out before I lightly cleaned up the seats with a stick and compound just to ensure they were seating correctly. I was very careful not to 'wheel the seating surface of the valves, just the tops and on the stem bottoms. After starting with the rough compound, the valves and seats looked like a dull gray. I eventually made the seating faces much shinier with the fine compound. I made very sure to clean the lapping compound from out of the runners because you don't want to lap your valve guides for the next 100K miles. After cleaning everything up I re-assembled the head with new seals and break-in lube. I also made sure to put everything back from whence it came due to the established wear patterns. At this point I was nearly ready to torque down the head, so I tapped all of the threaded bosses in the head and cleaned up the fasteners (MORE wire wheel) and blew out the passages in the head. BTW my cloth/wire wheel motor was a yard sale (washing machine) item I picked up for a couple of bucks and hold to the bench with 2 vice grips. I wiped and blew out the cylinders before wiping the walls with break-in lube for a smoky puff of insurance. I torqued the head back on in accordance with the factory manual in re. to pattern of tightening, but I make it a practice to sneak up on the torque figure in thirds of the total in order to get a better more uniform seal. Man! It looks like it could run soon! Next I will be messing with the exhaust/intake assembly which I have been spraying with Liquid Wrench for weeks now so I have a fair chance at no snappage. I think I will use the exhaust gasket supplied with the kit, because it seems like a real good idea to me. I *MAY* also rebuild the carb esp. if I can dig up any upgrades to do to a stock BBD. Or, I may start reviewing my carb basics in my excellent "Rochester QuadraJet" book that I learned a lot from and apply it to Mr. Carter. Do most of you find that this carb runs rich or lean in general? Part Eight I think the last post on this topic was back in March, but that was before my truck developed an appetite for transmissions. Well here we are in November and I finally found the time to finish the 258. The last part on the web site was where I torqued down the head so I will take it from there. When I tore the 258 down, I made sure to put my pushrods through a piece of styrofoam so that they would stay in order for re-assembly. As I dropped the pushrods back into place, I made sure that they were thoroughly coated on the ends with assembly lube. After checking to see if they were seated on the lifter and in the rocker correctly, I tightened the rocker bolts to the factory spec. When I tore down the motor, I was surprised to find that the valve cover had no gasket, but had copious amounts of RTV gripping the cover like grim death. Hey- it obviously worked since the block was clean. I however wanted to try the gasket, so I had already been working with a tube of that copper RTV, so I figured I'd try it, since re-doing it is not hard at all, esp. on this motor in a truck. I RTV'd the gasket to the head, let it cure a bit and then RTV'd the top of the gasket and put the cover into place. When I torqued the cover down, I wiped the excess RTV back into the head/gasket/cover to really get a good seal. One word of caution here-even though I knew this as I was doing it, I still over tightened the cover and kinda sucked the gasket back under the cover a bit. I used enough RTV that it shouldn't matter, but the point is that you don't have to go Herc. on the cover as it will push the gasket around. I then flipped the motor over on the stand and had a look-see at the oil pan situation. I ended up cleaning the gasket surface on both the oil pan and the valve cover with a wire wheel. This works great and removes RTV in a snap as opposed to scraping your brains out with a blade. BTW, I remember using Scotch Brite to prep the head/block mating surfaces. To replace the oil pan, it's probably a good idea to put the timing cover on first, so I drove the crank seal out from the back by catching the edge of the seal with a screwdriver. There is a relief cut into the cover for this purpose. I reinstalled the seal with High Tack around the circumference and pressed it in with a vice and a 1 3/4" socket which fit the OD of the seal perfectly. I went back to the block and scraped the cover gasket which-I mean you wanna talk about gorilla snot, OK maybe not... Using High-Tack, I positioned the gasket onto the block, waited for it to dry and torqued down my wire-wheeled bolts that I slathered in a Permatex goo that's made for bolts going into the water jacket. I noticed at this point that my cam was not perfectly aligned with the lifters, so I called Crower, and they told me that this is the way that the cam-to-lifter relationship should look. Before I talk about assembling the oil pan I should mention that there seems to be several different schools of thought on gasket prep. and the use of RTV and other schmutz. Some guys recommend using NO goo at all, and in some applications I think that this is smart. (Like tight clearance pumps and such) I have heard of for example soaking a tranny pan gasket in ATF before the install so that the gasket is swelled and won't wick anymore fluid. I think that you have to assess the situation for yourself and use your best judgement. I ended up using High-Tack on the cork gaskets and a little RTV at the gasket unions. I also used a bit of High-Tack on the rubber timing cover to oil pan seal. After I torqued the oil pan to factory spec., I flipped the motor over and began to prep the block for the manifolds, fuel pump, and accessories. I didn't actually mount the accessories on the front of the motor in the end because I still have to move it out of my basement, and I don't want any of my biker buddies using the distributor or whatever for a hand hold. In fact, I have two rough cut oak beams that I am going to drill so that four of us can carry out and up the steps safari-style. Next time- the 258 sees AMC blue. |
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