Series II-Stage II gerotor front cover progress

[CTX-SLPR]

Howdy ya'll,

I made a ton of progress tonight on my front cover since I finally got all of my stuff moved into my new house. Since I don't own an aluminum welder and I like to do things on my own, I've decided to make my cover a 2 piece atleast for a try. I'm too tired to take pictures of what I did but lets just say it looks good. Pictures tomorrow afternoon because I need to get some nailpolish to check my fitment and I'll take pictures before I put it all together.

 

[49-blues]

Cant wait to see the progress.

 

[CTX-SLPR]

Ok, these pictures are taken while the JB weld is setting. I'm filing in the small gaps between the upper and lower sections with some JB weld so its a good tight fit. Sorry the pictures aren't better but the garage has poor lighting for pictures and I don't have a tripod.
Picture 1: Overall from the front, you can see how the larger Stage II dry sump cover overlaps the smaller FWD Series II cover. The painters tape is to keep the JB weld from sticking to anything its not supposed to and I used a lot of it for rough mock up and machining out the bigger sections with a high speed cutter on my dremmel.

Picture 2: Shot from below so you can see how big the gap I'm going to have to fill is.

Picture 3: Sorry about the quality, but you can kinda see where I notched the lower section of the drysump cover to fit over the oil filter adapter area of the FWD cover

Picture 4: This is the otherside and yes the FWD cover goes under the Stage II cover where I notched it out, again notice the gap over the center section.

 

[CTX-SLPR]

Ok, here's some more stuff about the project. Since this is a production block and I'm external feeding it I needed to acess the main oil gallery and I had my engine machinist, "Ohio" George Montgomery drill and tap the old oil pressure sensor hole open. Well when he did that it broke through to water on the underside of the waterpump hole and he ended up having to machine a billet fitting that goes about 2.5in into the block and has a 3/8 NPT end on one end and is threaded into the block with a copper crush washer on the other. The tube is staked in place by a plug in the old oil feed port on the front deck and brazed in place. The waterjacket is sealed with epoxy.

The reason for the external feed is shown in the next series of pictures. the waterpump bolt pattern is the same for the new FWD cover so use the lower bolt hole as a refference. You can see the cover to block oil feed passage has been relocated inward about 0.5in and slightly up.

 

[49-blues]

What cutting method did you use to cut the covers in half? looking good!

 

[CTX-SLPR]

I used a bandsaw with highspeed aluminum blade on it. That Stage II cover however nearly overheated the blade since the side walls are over 1/3in thick! I'm debating between grinding aluminum or steel to fit the gap between them or casting it out of Marine JB Weld and backing it with a piece of sheet aluminum for the oily side of things. I'd really like to do it in aluminum but I've not got that size of a scrap on hand and I've not found an aluminum salvage yard here in town to get some from.

 

[SI/II3800Hybrid]

i've been a lurker for a while for my Series I/II 3800 hybrid project (talldeck SI/SII symetrical port heads) but this made me sign up...:biggrin:

any reason in particular you picked the Series II front cover? the series III has a new casting so GM saw fit to make some further design changes over the SII cover (i have a SIII also known as the L26/L32 that i plan on cutting up to further my research) there dont seem to be many reasons GM would change the tooling except for reliability or NVH improvements...

have you investigated the LG3, LN3 or Series I front covers? the reason i ask is they changed the cover to block galley passage location in the SII, the SI (& older) uses the 3.8 location... i still have more work to do but it seems that the SI pump scrolls are wider (see pic)

also how do you plan to drive the 6 spline SII pump? it may be easier to run the older SI pump as it is driven by two flats, it is probably easier to make a 3.8 crank sprocket work with the two flat pump than the 6 spline. i must note that GM switched to a tighter Tchain tooth pitch on the later Series I's (~93-96) and the SII than the LG3/LN3/early SI recieved, but undoubtedly your running an aftermarket 3.8 chain... (see second pic)

I've spent the last 4 years learning all of the changes GM has made to the FWD 3.8/3800 after i found that i could bolt a SII symetrical port head to a junk 3.8 (na) block...which has led to my talldeck/longrod SI with Symetrical port SII (not stg II kinda confusing eh? lol) heads.
so please forgive my intrusion, but your thread piqued my curiosity!
glad to see someone else is working on a hybrid

Regards, James

 

[CTX-SLPR]

Thanks for the pictures. The reason I chose the Series II pump was the improved pump design over the eariler Series I pumps. Particularly since the tollerances are more consistent with the pump being internally located vs the series I which had the inner gear located solely by the crank. As far as drive sections, I'm cutting the gear off of the lower sprocket and then machining the back of the balancer down to match the distance of what amounts to the spline drive spacer. Worst case if I need too much thickness on the spline drive spacer I'll put spacers under the crank sensor and get a custom crank pulley stand off spacer (the piece that goes between the balancer and the bolt on pulley ring).

If you do a search on this topic, I believe there are either 3 or 4 people that have made hybrid covers using either the VIN 3 FWD covers off of the classic 3.8 FWD or the Series I covers since they share the same deck height and front cover mounting stuff to include the cover to block oil transfer holes. They have however run into problems with double roller chains hitting the steel backing plate on the pump on the Series I covers if I remember Turbo1Dr's problems. He has a website detailing his build of his cover and KendallF started all of this atleast on the webboard with his VIN 3 Stage II drysump cover hybrid.

 

[CTX-SLPR]

Progress update, but first a correction. The water pump bolt pattern is the same but is moved down so the oil feed location is actually moved down slightly instead of up however laterally it has moved towards the engine centerline.

Well this last weekend the JB weld set (took 3 days in my cold garage) and the tape was a bit more of a pain to get off of it than I remembered but gasket remover took care of it. It turned out very well I think, the covers fit together very tightly but the top will come off over the top of the lower so it is a 2 piece setup. This week and weekend I've been making the spacer plate to fit between the sections across the middle since I don't trust JB weld for something that large and unsupported. I started out with a 6.25in wide by 0.25in thick by 0.5in wide piece of aluminum bar stock that I cut out of a larger piece I had in my scrap bin. Now this is where having a mill would have really paided off as there is so much hand grinding to get it close to flat and I'm going to have to skim it in JB weld again and then allow the gasket maker to truely seal it. I then ground down the backside of the timing over upper section to a constant flatness and then ground, sanded, and filed the ends to match up with the inside of the cover so I had to just barely tap it in with a deadblow. I then clamped it tight and drilled two 13/64in holes through the whole stack up and tapped the filler block to 1/4-20NC. The holes in the cover I reamed out to 1/4in so it would pull the filler block tightly to the cover. I then matched the edge of the filler block to fit over the top of the lower cover section pretty exactly, again by hand. I've got pictures of the pieces but since my bolts are too long I don't have a picture of it on the block. Those will come tomorrow just before I fill in the rest with Marine JB weld.

I think at this point my 6.5yr old Dremel has died but it has served me well so its just time to get a new one.

 

[CTX-SLPR]

I made a lot of progress last night on the balancer and reluctor rings but I also dropped the crank pulley assembly on my foot so I wasn't in the mood to post stuff and now its morning before work so this will be quick.

If you go to Turbo1Dr's website he has a lot of good pictures and information on his swap. As such he also ran into some issues with his balancers and oil pump drive. He was working with a stock balancer and machining it to work with the oil pump drive and at the same time he was adding the "quick start" reluctor rings. I also think he was using a Series I reluctor ring and balancer setup as a donor but I'm not sure that matters. I started with an Indy Lites balancer/damper (it actually has a rubber damper ring inside of it instead of a solid hub) and a 99 L36 balancer/damper assembly. The newer reluctors are required to clear the oil pump drive snout since the stock LC2 reluctors are smaller in diameter. I had a very fustrating time getting the stupid bolts that hold the reluctors in place out but once I got them out you can see that the bolt pattern on the Stage II balancer is prescent though not used on the Series II balancer and it bolted right on with correct indexing.
Turbo1Dr also has had problems with the balancer cracking on the keyway. Looking at how thin the stock type balancers are at the key way and how beefy the Stage II hub is I'm doubting I'm going to have that problem but only time will tell.

 

[49-blues]

Nice work!

 

[CTX-SLPR]

Well I hit a few snags today. I got the main bearing area of the block cleaned up and then taped the journals of the crank and securely but not fully bolted it in the block. I did this to check the timing chain clearance and just like Turbo1Dr did, the Billet Double Roller Rollmaster chain hits the back of the pump, mine hit even worse than his did. I am now putting that up for sale and am debating between the Edelbrock EDL-7829 and the Cloyes CLO-9-3132 as to what to try next.
I also found out that the 14 bolt oilpan I'm using won't completely seal the bottom of the timing cover off so I'll need to fabricate something to fill the gap. I'm thinking I should just get my hands on a busted 20 bolt pan and cut the nose off and then weld the section between the bolt holes onto the 14 bolt pan since I can weld steel, but not aluminum and I like keeping it DIY.
The final snag I hit today is that there is a rather significant difference in the depth of the rings and sensor location. I have 7/32in (0.219in) clearance between the sensor and the back edge of the rings however by my calculations to get the pulleys back to stock I need to machine 0.664in off the back of the balancer. That's 0.445in too deep for the sensor. Pulley alignment I can fix, I'm worried about the 0.508in extra of balancer bolt and balancer sticking out. Does that matter or will I need to machine the inside of the balancer down so the soulders for the washer is at the end of the crank snout like stock?