I then slot the head of the bolt so I can use a flat-tip screwdriver. I usually tap this hole with a 3/8" tap, and cut off the end of a 3/8" bolt. Here is the passage that must be blocked.
TH350 EXPLODED VIEW MANUAL
I prefer internally dual feeding because it leave out the additional gasket and eliminates that one extra possibility for a pressure loss resulting in burnt 3rd gear clutches (Yes it has happened to me).Īll transbrakes will require dual feed of the direct clutch, as well as many manual valve bodies. It is accomplished by most valve body kits without doing so internally but requires a "transfer" plate and gasket to be added under the support plate in front of the valve body. You can do this on any rebuild but you must also block a passage in the case near the pump to prevent loss of pressure to the reverse circuit.ĭual feeding doubles the area of the piston that has pressurized fluid on it in 3rd gear, more than doubling the capacity of the clutch.
TH350 EXPLODED VIEW INSTALL
On a stock rebuild you would normall install this lip seal. This is part of the process of "dual-feeding" the direct clutches. This is a hi-performace TH350 and I did NOT install a lip seal in the drum that would seperate the two halves of the direct piston. Take note of the orientation of the seals, the lip will face towards the "oil" side of the piston, not the clutch side. 040", and will work with quite a bit more, but excessive clearance can result in delayed engagement, busted lip seals, and unsatisfactory shift quality. It will work with less, I wouldn't go less than. So a 5 friction direct setup would work great with. Rule of thumb on most auto trans friction clearances is ~.010" clearance per friction. Ideally you would pre-assemble, and check clearance using a 4 clutch pack, meaure the additonal thickness of the extra friction and steel, then cut the exact amount needed to leave you the exact clearance you desire. Stock measurement is ~.835, I cut them to. If you need one email me and if you can supply a core, I MAY be able to sell you a piston. I try to keep a few machined on hand, and machine several at a time when I do so. This can be accomplished on a brake lathe. 160" to allow for one extra friction and steel plate for a total of 5 frictions, and 5 steels in the directs. In the rare application that does not need reverse or low gear engine braking the low piston and low clutches can be deleted, and the feed holes in the case blocked.įor racing and heavy towing use, you will want to machine the direct clutch piston down approximately. The low sprag (low roller clutch actually) causes first gear when only the forward clutches are applied.
The low/reverse clutches do not apply in automatic range 1st gear. Manual low gear creates engine braking on deceleration. This allows reverse when applied simultaneously with the direct (high gear) clutches, and allows manual low gear when applied with the forward clutches. Its function is for oil to force it towards the front or bellhousing side of the trans, applying the low/reverse clutches. The first item to go in wil be the low/reverse apply piston. Once the case has been cleaned, all threads checked and or repaired, and the rear case bushing installed you can start assembly. I would recommend you get at least 2 additional sun gear bushings individually also. Might as well order a bushing kit, as well as a thrust washer kit. That said I hope this helps some understand the TH350 or maybe it'll help when you're elbow deep and have a question.Ī TH350 is known to be rough on bushings.īushings are critical in that they allow the rotating parts to ride true on center, and for the lube to make it to the rear of the trans.īe prepared to replace almost ALL the bushings in a TH350.
TH350 EXPLODED VIEW FULL
I may not always be available to answer questions, full time job, full time college, multiple car projects, and a family take alot of time. I am not doing a step-by step pictorial, don't assume I have shown where every part goes, there will be some thrust washers I have installed and not taken an individual picture to show it because of bandwidth considerations. This is an ongoing project, I will add to it as I go.
It has good pictures, alot of good info, but has some outdated info. I would recommend Ron Sessions book "TH350 Handbook" in the HP Book Series. First time builders will likely need a tech manual. I do not intend for this to be a replacement for a tech manual. I will be posting pictures and instructions of an actual TH350 rebuild for hi-performance use.
0 kommentar(er)
