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Discussion Starter · #182 ·
thanks!

looking forward to getting it running soon with my twice the power motor. :mrgreen:

so ive decided this is how im going to do my new shutoff arrangement. Its brutally simple and elegant.

Watch how the owner shuts down his nissan with a mercedes diesel and the same vac shutoff-


all hes done is run a direct line from the vacuum pump to the shutoff valve, T-ed into it, and run a vacuum line to the dash which he glued into place. When he holds his finger over the hole, he closes the vacuum circuit, and the engine shuts off.

Its spectacularly simple and effective.
 

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Discussion Starter · #183 ·
So close on the MB fan!

It fits between the motor and radiator like it wants to be there-



except for-



Looks like im going electric. Otherwise id be cutting down each fan blade by 1.5 inches to clear with enough room with the engine moving. I doubt that would be worth the time over just finding something electric approximately 18 inchs across

 

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Discussion Starter · #184 ·
wow check this out-

just about ready to fill the cooling system on the 617 and popped the overflow tank cap.

Looks like the 616 must have developed some kind of secret head gasket problem. No running issues, ran really well and at about 165 degrees average no matter the load. Started in really cold temp no problem also.
Also weird as no brown gunk in the radiator cap either and the coolant looked good. I know this is new because this tank was clean when I first did the conversion.

It has to be motor oil, there is nothing else it can really be. Kinda messes up my plans for that motor, but its on a stand, so replacing the head gasket can come with replacing all the leaking seals and timing chain as well I guess.

 

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Discussion Starter · #185 ·
it lives!

Just need to work out a leaking brake fitting, but its ready to test drive.

first start, air problem


second start, rebled the air issue and it runs great!
Also got to try out the open vac line shutoff, boy is that effective. Psyched to go for a test drive now

 

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Discussion Starter · #186 ·
so some other pics I forgot to upload related to the 617 vs the 616 installation.

Aftermarket electric fan I bought off amazon, its actually quite nice for the 30 something dollars I paid. (!). It also had great reviews, im interested to see how it holds up, and i have it rigged for a manual on off right now until I work out the temperature controls and rig something up.



fits pretty nicely with the 617, good amount of space-



I had to get a little interesting with the coolant passage that comes out of the driver rear of the head. On the 616 I went up and over, but that created a lot of room issues for the air filtration, so this time decided to go down, under, and around.

It travels behind the oil filter, around the lower oil pan, then up to the connection under the climate control airbox



also made a slight, but very important change that I neglected earlier. The GM radiator uses an upper and lower fan shroud as a clamshell to hold the radiator in place, with the 616, the lower shroud was brittle and shattered, so I only had a modified upper shroud.
For 8 thousand miles ive been driving around with the radiator staying in place only by the stiffness of these rubber mounts in the lower position, with no additional support to them!-
Fortunately some metal tabs worked perfectly to support the rubber and prevent an eventual disaster




Here is my stock benz downpipe-



I have to do a little follow up work here, as you can see the bellows mount is broken and loose-




I was able to extract the broken bolt and am working on remaking or repairing this bracket.
I have it bolted up with the upper bolt and have the exhaust almost done, but I definitely need to return and fix this long term
 

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Discussion Starter · #187 ·
finally time for me to put some tires on this thing!

Right now I have P205/75 R15s
With the 3.5 body lift, id like to go with a taller beefier looking tire that fills the well a bit better than this

any suggestions on size?
 

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Glad you're getting the bugs sorted out. Now you have a 3.5" lift but don't you also have 2" drop spindles? Works out to about 1.5" lift? Anywho, the 1st gens can usually get away with 235/75 R15 with minimal rubbing at stock height (mine), so a little lift should allow that size with no problem (but as with all things, YMMV). The 235/75 R15 are found in a variety of styles and are usually on the cheaper side, so that's my recomendation.

-Andrew
 

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Discussion Starter · #189 ·
icebrrg3rd said:
Glad you're getting the bugs sorted out. Now you have a 3.5" lift but don't you also have 2" drop spindles? Works out to about 1.5" lift? Anywho, the 1st gens can usually get away with 235/75 R15 with minimal rubbing at stock height (mine), so a little lift should allow that size with no problem (but as with all things, YMMV). The 235/75 R15 are found in a variety of styles and are usually on the cheaper side, so that's my recomendation.

-Andrew
Ive been looking at pics here, and yes, the 235/75 R15s look awesome. Im sold.

Gonna order up a set, thanks for the tip!
 

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Discussion Starter · #190 ·
I have good news and bad news.

The good news is that a 617 in front of a 4.56 diff with street tires is an absolute blast to drive. I need to race this van against the wifes wagon, but I have a feeling it might hold its own until 65mph at least. Third gear = zoom. The motor has plenty of power to throw it around, Ive been enjoying myself.

The bad news-

The transmission must come down again as I believe I have bolt to flywheel contact again, just like the first time. Its making that same horrendous noise it made in the very beginning, and ill be playing again with spacers. Oh well, at least I have this down to a science at this point.
 

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Discussion Starter · #192 ·
DRZ said:
how did you hook up the fan?
Its just switched on the dash at the moment. Im waiting on some metric threaded port to pipe thread adapters so I can put aftermarket temp sensors in and rig up a temp switch for it to come on automatically. Also for my new and better temp gauge, which isn't installed yet on this motor.
 

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Discussion Starter · #193 ·
going to go look at a POS rusted out 1996 1500 parts truck that has the NV3500 (hopefully, seller claims).

Ill never figure this depth issue out if I don't compare the transmission bell and input shaft depth differences with both transmissions side by side. The adapter is made for the NV3500, so I should be able to get some good measurements and either get the T5 to be exactly correct, or just use the NV3500 instead and put the T5 in something else.

Fortunately, there are no shortage of 500 dollar 5-speed rusty chevy trucks on craigslist at the moment in the correct year ranges.
 

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Discussion Starter · #194 ·
Tirerack claus came through and some rubber has arrived-



these tires really fit on the front of these vans? wow, the size difference is astonishing, looking forward to having them installed as soon as I get the tranny put back up

 

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Yup, they fit, minor rubbing on full lock turns, I'm not sure of the backspacing on mine, and they are truck rims and they're probably 8" instead of 6 1/2 or 7" wide. I did "tap" a little on one inner fender to eliminate a rub, but I have no lift and I'm sure I need new body mounts.

LeftFrontSmall.jpg


-Andrew
 

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Discussion Starter · #196 ·
looks good!

where did you get those rims? what source vehicle? (just in case, I have stock steel wheels, and maybe all these conflicting accounts has to do with so many different rim options out there)
 

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Discussion Starter · #197 ·
so, some developments-

I have been in New Venture gearbox mania. I sourced a NV3500 gearbox out of a 1994 chevy 1500 6 banger, and in the process of finding the correct gearbox, also grabbed a 1999 NV1500 out of a 99 S10 4 banger.

The original purpose was I couldn't find a non 4x4 NV3500, so was looking for a possible tailcone swap candidate, but it turns out they can't really share that part between the two gearboxes. However, keeping it around as it looks suspiciously close to another benz diesel family OM60x bell pattern.

Starters on the correct side, though a bit too low. Worth hanging onto and taking a look down the line. Maybe an s10 with the NV1500 would be an good swap candidate for other families of benz motors.

Returning to the NV3500, I lucked out looking at a 4x4 gearbox and transfer case, the guy turned out to have a 2wd sitting under a work bench unadvertised with about 100k on it.

here are a few pics of the gearboxes-

s10 on the left, 1500 on the right (with the correct 6 and 8 cyl bell pattern I need)



notice the different locations for the shifters. One of the other reasons for grabbing the s10 gearbox was moving the shifter back if I need to, but I don't think its possible or necessary. We will see soon enough-



The NV3500 has an external slave like the T5, but its clear on the opposite side of the bell under the starter, so some re-routing will have to occur if I swap gearboxes. Looking on the van, there appears to be enough room, interesting location for it though



Also another development is I mounted these huge tires. we will see if it can turn, I remain in possible doubt with the stock wheels. The size difference is not small. :mrgreen:



Looks like it might be a little tight in the front-

 

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Discussion Starter · #198 ·
well, bit of a head scratcher to ponder now.

Ive pulled the thing in to dozens of parts again, and I cannot find a single physical issue with the clutch that would be causing the awful noise I heard. like the gearbox starting to eat itself.

Ive also finally had a chance to compare the T5 gearbox with a NV3500 gearbox, and there is no difference between the input shafts as far as depths.

The input shaft on both gearboxes extends 2/8ths past the bell, and the splines start 5/8ths down the shaft. This brings into question some of the early issues i had with the adapter kit, like the pilot bearing adapter wasn't going to work for the NV3500 either.

So now im thinking about taking the T5 apart and looking inside. The noise was awful, and ive found nothing external that would explain it.

If I want to use the NV3500 I now have, I need to change the clutch disc to the correct spline clutch, get a new slave cylinder that matches this bell, and cut another shifter hole for it.
 

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Wow, That thing is sure putting you through the wringer. Progress is the cause of a lot of our trouble but it's usually well worth it when one finally comes out the other side. Hang in there, you will have a rare piece that fits your needs to a "T" at some point... Stan M
 

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Discussion Starter · #200 ·
DRZ said:
Wow, That thing is sure putting you through the wringer. Progress is the cause of a lot of our trouble but it's usually well worth it when one finally comes out the other side. Hang in there, you will have a rare piece that fits your needs to a "T" at some point... Stan M
whats most irritating is that 100% of my drivability issues with this conversion have to do with trusting the provided parts of a purchased adapter kit, vs making one.

Im on 5 different removals and reinstallations of this T5, all related to what I now am aware is an incorrectly depthed pilot bearing adapter. Its just not designed properly, its much too shallow a mounting point for a stock GM pilot bearing. Had I just figured it out for myself and made my own adapter using a GM flywheel, I wouldnt have been in the position of redoing it so many times.

Now that im in the mindset that every part of the adapter kit might not be designed perfectly, im much more likely to get this figured out for good, but in the process may have damaged a gearbox that only has 8k on it since being rebuilt. Oh well.

Just goes to show, anything worth doing, is worth doing yourself.
 
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