TyrannicalTy

Hi All,

I am the excited new owner of a Class C Motorhome built on a 1985 Chevy G30 van frame with a 350 V8 with 61k on the clock. My wife and I plan to take it out west this summer, so I'm going through it and tending to all the maintenance items I can think of. I typically do my own wrenching. However, an old-school Chevy is a completely new animal for me, and I know I have a lot to learn from you good folks. Anyone know any common pitfalls or points-of-failure for an '85 G30 that I should take care of before embarking on a 5700 mile trip?

Initial baby-steps in the first week:
1. Obtained a Haynes manual on Chevy G-Series vans. Very helpful!
2. Changed oil/filter using Mobil1 10W-30 and K&N Filter
3. Replaced air filter(WIX). Painted rusty filter cover for good measure.
4. Replaced fuel filter(WIX).
5. Replaced Cap/Rotor/Plugs. Brings me to my first question:

Spark Plugs - RockAuto said AC Delco R45TS plugs should work. However, the old plugs were AC Delco R44T plugs. I've since learned that T = Tapered seat and S = protruding tip in the AC Delco nomenclature. The engine seems to run fine with the new plugs. Will the protruding tip cause pre-ignition or other problems?


The idle seems to be a bit fast, so I ordered a tachometer to install, and will adjust the idle down afterwards. I assume a good target is 700-800 RPM at idle?

Also on my to-do list:
1. Trans fluid/filter
2. Coolant, t-stat, upper/lower rad hoses
3. Rear diff fluid and gasket.
4. Also need to inspect brake system, but don't know anything about drums or duallies...

All pointers appreciated. Thanks!

canucklehead

You are lining up the wrong end of the spark plugs. The taper at the end of the threads is the distance they will go into the block. Those look the same, but on has a longer ceramic part.
My vortec calls for iridium plugs. Some older engine run fine on platinum or double platinum.
As for the rear brakes. Do yoou have a semi or full floating rear axle? Look that up in the haynes manual. If yours is only on the engine, pick up one for the chev van of your year.
If you don't want to handle pulling the axles to do the brakes, then it might be worth paying a shop to do it. Rears will last you years....

TyrannicalTy

Hi Canucklehead. Thanks for your tips.

Spark plugs - I realize the treads and taper seat are the same between the two, but the R45TS has the protruding tip. The longer body doesn't matter, I just wanted to know if the protruding tip would cause engine interference... Researching the issue more, a lot of 350 small block forums recommend the R45TS for most factory engines, but it really depends on what headers you have. As far as I know, my heads are original and the engine seems to run OK with these plugs installed. If I'm wrong here, someone please tell me

Manual - Yes, I bought the Haynes repair manual for Chevy and GMC Full-size vans, '68 thru '96. There are a lot of variants covered, but so far it's been really helpful.

Rear Axle - I think mine is full-floating rear axle, which is what I would expect for a motorhome. Full-floaters are better with weight, right? I removed a rear hub cap and my axle has bolts on the end similar to this (not my actual vehicle):

So far as I know, that means it's a full floating axle, correct?

Thanks again!

canucklehead

Pretty sure. I have never tackled one, so if you are not confident, it might be worth paying a shop. Then, you can also do the seals, fluid, rear brakes and turn the rear drums all at once. Then, don't touch it for years.

canucklehead

If you are in any way unsure of the the spark plugs, just call a chev dealer. They will tell you exactly what type, and what metal ( platinum, double platinum, iridium, etc...)

TyrannicalTy

So I haven't gotten to the drums yet, but I did remove the front wheels to inspect the pads/rotors. I have new Wagner pads on hand, but it looks like there's plenty of pad left on the current set:

Rotors look good. No scoring or gouges. Good thing too, because replacements are pricey for that behemoth! I also ordered an adapter for my Motive Powerbleeder, so hopefully I can change the brake fluid soon and take out some of the sponginess.

Other thing I got done: I installed a cheap aftermarket Tachometer. If anyone else is looking into adding one, I've marked up some details for your typical 3-wire tach:
You simply splice in the three wires as shown at the distributor. Couldn't be easier!

My idle is just below 1000 RPMs in Neutral, but it drops down to 700ish when I put it in Drive or Reverse. Seems to be OK, so I'll leave it for now.

timatoe

I just did the brakes all the way around on my '85 Minnie Winnie on the G30 chassis. I would highly recommend just paying someone to do the rear. Drums aren't that difficult but on these you've got to pull the axle shafts, have a special socket to get the flange nut off ($36 on Amazon) then brake parts, re-assembly etc. and then I had a heck of a time getting them adjusted (still don't know that that is right). Fronts were super easy, I'll pay for the rear next time.

upnorthexpress

Hi Everyone,

Trying to resurrect this thread, hopefully, that's ok!


New to the forum and a new owner of a 1985 G30 Rockwood motorhome like the original poster above. The info above is fantastic! I'm mechanically inclined and have done head gaskets, transmissions, and other odds and ends on a number of cars and trucks. I bought the rig with a blown head gasket/ cracked bock. Previous owners had it since new for - 35 years and then sold it to friends kids who had it for just over a month... Drove it to Yellowstone and toasted the engine. I've got a new to me 350 I'm going to put in to replace the blown engine but looking for info as I've got to get it towed from Wyoming to colorado to my driveway.

Can anyone answer a few questions? I've searched but not found very helpful info yet. Its 300 miles away and I looked at it after a very long day and wasn't thinking clearly to get photos of the drivers door tag with info, and the title has no really helpful info on it either.

I am trying to find out -

- Gross overall weight for it
- Wheelbase
- Wheelbase width - for car hauler option. - thinking of disconnecting the driveline since its rear-wheel drive, so it frees up the rear wheels, any issue with this?
- Height
- Any tips or tricks for removing the engine and swapping a new one in.
- any other quirks or things to watch out for as I get this beast back to life.

Do you think if I get the heads machines and checked they would be ok? the grandkids I bought it from said it did overheat, and enough to crack the block and melt the coolant reservoir... I talked to the mechanic at the shop they had it towed to and he said the block is cracked on the left side and water pours out when you attempt to fill the cooling system.


Thanks for all your time and energy.

Best

Pete

Any help would be greatly appreciated!

Weldlife

I don't know what your situation is but my g20 van only has a stock radiator trans cooler that sucks . As I was replacing the filter on the trans I put in a deeper pan to hold more fluid and added a trans cooler to it .

The cooler was pretty simple. All I did was tie in an additional cooler with some brass fittings and trans hose so the fluid would pump thru the stock cooler, thru the secondary and then back to the pan .

As for the deeper pan I went the cheap route and pulled a later model 4l60e pan to put on my 94 model giving it an additional quart capacity. You would probably have to buy a aftermarket pan for that which could be pricey .