Cardinal Grammeter Posted August 15, 2015 Report Share Posted August 15, 2015 I'm actually attempting to find all the wacky emissions stuff for my 620 which was massively stripped. I acquired a complete EGR sub-manifold (Jersey) but do not have the tube. I have both ends with some tubing that was crimped shut - so I could butt weld new tubing to these ends - or simply find new tubing and bend and flare it. Most people go out of their way to eliminate all this clap-trap - but I'm going the wrong way (!) Looks like a new tube assembly if available is something like $35 which is kind of pricey. So what do people do if they have to repalce/fix this tube? (Was thinking they have these SS bellows tubes for hot water tanks. VERY bendable - but probably too big in diameter.) Quote Link to comment
flatcat19 Posted August 15, 2015 Report Share Posted August 15, 2015 Reason why you want to put all the smog equipment back on? Quote Link to comment
datzenmike Posted August 15, 2015 Report Share Posted August 15, 2015 I would advise leaving it alone if working and the same if not. If the tube is broken, be sure the EGR is disabled. You do not want ordinary air (now with 20% oxygen) getting in and messing with the mixture. 1 Quote Link to comment
Cardinal Grammeter Posted August 15, 2015 Author Report Share Posted August 15, 2015 Why am I doing this is a good question. I want to be able to look at this 620 and see no evidence of all the stripping and butchery that was done to it. It's not a restoration but rather, a reassembly. This got out of hand when Jersey started supplying me with anything I could think of. So the butchered EGR/manifold (busted casting boss at EGR tube fitting and epoxied shut, blocked off EGR, missing solenoid, mangled throttle cable bracket) was now available. He even got me the weird emission control Combination Valve I think they call it. Remember, this 620 had a axe butchered Rochester MonoJet 1-bbl and I had to work pretty hard to an proper affordable Hitachi carb for it (I now have 3 of them I think plus extra parts.) I was a mess of epic proportion ranging from boogered carb, coolant lines, EGR, emissions, air cleaner, fuel lines, etc. etc. So I'd like to get it back to OE stock - Jersey even got me the fuel filter bracket and the windshield washer tank/pump and bracket which is unique for the 1974. Finding parts for the bastard 1974 is daunting. So I guess it is a challenge. And looking at the result is inspirational - yeah, I know, probably a touch of OCD. Quote Link to comment
Cardinal Grammeter Posted August 15, 2015 Author Report Share Posted August 15, 2015 It's more like trying to complete a collection of Morgan Silver Dollars. It's like after forty years, it is rare to see one that has remained intact - it could be a worn out rusty truck, but it would still be impressive - especially for the unique 1974 transition model. Quote Link to comment
datzenmike Posted August 15, 2015 Report Share Posted August 15, 2015 Why am I doing this is a good question. I want to be able to look at this 620 and see no evidence of all the stripping and butchery that was done to it. It's not a restoration but rather, a reassembly. This got out of hand when Jersey started supplying me with anything I could think of. So the butchered EGR/manifold (busted casting boss at EGR tube fitting and epoxied shut, blocked off EGR, missing solenoid, mangled throttle cable bracket) was now available. He even got me the weird emission control Combination Valve I think they call it. Remember, this 620 had a axe butchered Rochester MonoJet 1-bbl and I had to work pretty hard to an proper affordable Hitachi carb for it (I now have 3 of them I think plus extra parts.) I was a mess of epic proportion ranging from boogered carb, coolant lines, EGR, emissions, air cleaner, fuel lines, etc. etc. So I'd like to get it back to OE stock - Jersey even got me the fuel filter bracket and the windshield washer tank/pump and bracket which is unique for the 1974. Finding parts for the bastard 1974 is daunting. So I guess it is a challenge. And looking at the result is inspirational - yeah, I know, probably a touch of OCD. Hey I totally agree with you. If it can be done go for it. The '74 710 EGR tube was the same as used in the '74 620 there were no others. The L18 was only used for about one year and the early ('73) 610 didn't have it. The tube is stainless I think to better withstand the corrosive nature of the exhaust gasses. When old they are very brittle... and they still rot out. Thin flexible pipe won't last. Best thing is something thicker bent in a loop so it flexes slightly. After '74, the washer reservoir is on the firewall. Earlier tuucks were on the rad support where the later charcoal canister went. The '74 tank and mount was different from the '73 being taller and with the integral pump on the back or mount side. Here's another unique thing.... If you have a 4 speed the flywheel is a 5 bolt mount just like all L16s and L18s but it takes a 225mm clutch. Only the '74 620 has this. Quote Link to comment
Cardinal Grammeter Posted August 16, 2015 Author Report Share Posted August 16, 2015 And to think, 40 years ago, when I had a 510 and B210, I had gotten an L-series engine factory service manual (L18 is not in it) and a 1974 620 service manual from where, I don't remember now. I thought about selling them every now and then, but as usual, I never did. So I have the SM with a great story for this project. And I can't imagine where I'd be w/o Jersey's help. For example: they blew a bolt and nut through a hood hinge pivot. So I asked him if he could get me the shoulder bolt. He did - he sent me both. But no nut. I mentioned the nuts because he was always meticulous to include the fasteners for anything he pulled. So in the next package, he cut out the nuts that are spot welded to the hinge bracket. Quote Link to comment
Ericthenorse Posted August 16, 2015 Report Share Posted August 16, 2015 I am going to be yanking my motor in the next few weeks(also a '74) You are welcome to any of the emissions parts you need.... Are you in a big rush? Is this all that's holding you up? Quote Link to comment
Cardinal Grammeter Posted August 16, 2015 Author Report Share Posted August 16, 2015 Ericthenorse, Thanks for the offer! I definitely need the EGR tube. Let's move this to PMing - I'm sending you one now. 1 Quote Link to comment
Cardinal Grammeter Posted November 6, 2015 Author Report Share Posted November 6, 2015 Eric has gone silent... EGR tube is now main hurdle to getting engine fired up (other than getting the vacuum hoses sorted out.) Took over an hour with oxy-aceylene and parafin to get the fitting and smashed shut tube out of the exhaust manifold. VERY DIFFICULT. Had to do many cycles of heating nut, heating boss, and heating nut with heated boss. Heating the nut near welding temp produced some "kinks" on cool down - each cycle reduces the thermal conduction through rust so subsequent heating reaches further into the fitting. But did get it free and removed. Surprised to see that the manifold fitting is compression with a ferrule! (A single flare is used on the "cold" end.) I thought it was 1/2" which really didn't make any sense, but it is 12mm. The price of stainless steel tube is totally insane. Over $200 for a 1m length. McMaster had a 0.5m piece for $85. HaHaHa. Like that will ever happen! I have some 1/2" hydraulic steel tubing and am considering turning down the ends and using. Yes it's steel but I don't think I'm going to wear it out since it will be a 2nd/utility vehicle. (Actually, I could drill out the fittings so it takes the 1/2 inch. If I find an EGR tube, it will have the fittings. So the only use for these fittings will be to use on a DIY piece of tubing. I think 1/2" is cheaper than 12mm in any material. And since I have some fairly heavy steel 1/2 inch, maybe drilling them out is not a bad ideal. Then there is the ferrule issue.... ______________________ EDIT: Since I'm just trying to get this 620 on the road, for now, I think I'm just going to plug both ends until I can find a L18/20 tube Quote Link to comment
DanielC Posted November 6, 2015 Report Share Posted November 6, 2015 Try these guys. http://www.mandrel-bends.com/catalog/ Quote Link to comment
Cardinal Grammeter Posted November 6, 2015 Author Report Share Posted November 6, 2015 DanielC! Best prices around for 1/2" OD SS tubing - like $6 a foot. If they had 12mm, I think I'd just buy the tubing and do it proper. EDIT: Thinking.... Finding an old one could very easily be ready to crack. It would be trivial to open up the fittings to 1/2" and simply use fresh 1/2 inch. I they have 16 and 18ga - I think the 18 is $8 a foot. The 16ga would be .060 wall and I could actually turn that down to 12mm which would be about .045 wall, but with the reality of cracking probably not a good idea. Could buy some extra length and do a loop. 2' shipped is about $20. The only tricky part is the ferrule - maybe turn just turn the tip down for the 12mm ferrule... I think my options are: Wait for a used one - if EricTheNorse comes through, I'll have one Fab one from 1/2 new SS Just put the plugs in for now and get running - worry about this later. QUESTION: When they crack, where does the crack form? where the tubing emerges from the fitting? ...or? Quote Link to comment
datzenmike Posted November 6, 2015 Report Share Posted November 6, 2015 Stainless is used for it's corrosive resistance. Exhaust is very corrosive. Hot metals oxidize even faster. Quote Link to comment
Cardinal Grammeter Posted November 7, 2015 Author Report Share Posted November 7, 2015 Yep, know about stainless properties. On my engine exhaust manifold, they cut the tube maybe 4" from the fitting and crimped it shut. That piece of tubing is in perfect condition. Same on the EGR fitting end - about 4" then tube was cut and in great shape. So I don't have any indication of where they crack and fail. Maybe a good used one would not be that hard to get? I did notice the L18 tube seems to have simply a 180* bend while the L20B has zigzag with (3) 180* bends - clearly they were trying to build some flexibility in the latter design so the suggestion to put a loop (which is also (3) 180* bends) makes lots of sense. I also got a good look at that L20B tube and I think it could be used on a L18. The only fly in the ointment is that they used a compression style fitting at the exhaust manifold which involves a stainless ferrule. That particular part is a real problem. I've been trying to come up with a way to machine one and it is a real chucking challenge. Quote Link to comment
datzenmike Posted November 7, 2015 Report Share Posted November 7, 2015 The tubes I have seen on the Z series, rotted from the inside out. If oxygenated air gets in the engine will run lean, poorly or not at all. Longer with bends makes it easier to remove and the exhaust gets cooled slightly. Steel will work for this, may not last as long but more than enough. Cutting and crimping is just a waste of time unless it was leaking. It's far easier to just pull the vacuum line off the EGR to disable it. Quote Link to comment
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