Hope you don't mind me "going public" with this...I am going to go down to the shop today, and try to get the info on the brackets and mufflers. Basically, what they do at our shop is to substitute a D7G muffler for the stock "California Muffler" cat installs, and saves about $700 per muffler.It also greatly simplifies mechanical repairs and doesn't build as much underhood heat...both the D7G and 627B use the 3306 diesel inline 6 cylinder. It does require cutting a new round hole in the hood for the new stack to go through. For now, here's a few pics of the muffler set up on the D7G, this one was rigged up with a cable plow, which is interesting in itself. This should also work on 621B/623B's, as long as they have the 3306 engine. Some later 621B's and 627B's have the 3406 installed, I was told that they were usually used in auger scrapers. Stay tuned......
A couple of pics of the cable plow for you.
Great pics. Further on 3306, Cat mufflers are designed to rust out to ensure spare parts sales. I cut one apart years ago and made copies in Stainless steel for 3306 as I had a few at that time. They outlasted the machines. Another good hint for 3306 owners is to replace the original exhaust manifold studs with stainless steel. (Make your own from threaded rod, we call it booker rod down under). Originals used to rust out and this fixed the problem. I still used the original Cat locking nuts and flat washers.......C ya......Ray
Bad news was...since it was friday before a 3 day weekend, the shop foreman was gone for the week. Also was told she'd been involved in a serious auto accident recently, she's OK but a bit beat up. It looks like rain is a good possibility through early next week (figures) so I'll probably get another chance to get drawings of the brackets soon. The guys in the shop told me a new cat muffler, standard 627B replacement, is up to approximately $1100 USD now! I wonder if Flowmaster has a muffler that would fit?! Ray's idea sounds like a good one too. Stay tuned....alan627b
At long last, I finally got the pictures. What outr shop does, is to have brackets made to use the D7G mufflers on our 627B's. I was wrong, at current prices, the D7 muffler is $300, the 627B is $2000!! This short elbow, part # 7N1756, (about $300 new at Cat) gets modified with a piece of stainless pipe. Our fab man machines the elbow to fit the ID of the pipe, then machines the OD of the stainless to fit into the muffler along with a sealing ring. It looked like he cuts a groove into the OD and uses a piston ring to seal it. The stainless pipe is a way to make the elbows last longer, I gathered the exhaust gas ate into the cast iron and shortened the life of the part.
The main bracket, 3 pics at a time....
3 more pics
More detail pics
more detail shots
Pics of the outlet and the bands that hold the muffler to the main support bracket.
More shots of the bands
Cat D7G muffler, PN#6N 0731, cat cost app. $300, so I'm told. The lower outlet is welded shut.
D7G muffler, pics of the assembly.
The final envelope.....last 3 pics of the final assembly (sort of!) For my next trick, I'll get some pics of what it looks like installed on the 627. It requires cutting a new hole in the hood, not a bid deal. Has the added advantage in that one mechanic can remove the muffler himself, no crane required. It also doesn't seem to cook everything under the hood as bad, and since the exit for the stack is no longer at the rear, doesn't cook the operator quite as bad either. Not appreciably louder than the original muffler, either.
Very, very nice fabricating job Alan... thumbs up to the people who did the work... quality looks excellent. All ways like looking at metal projects... thanks for posting the pictures. OCR
Thanks Alan, Thats a top class act to follow-really well done Neil
A straight pipe and some ear plugs would be much more affordable
Trust me. Pete, they're loud enough the way they are....WHAT DID YOU SAY???? alan