Intro - Oregon guy

Not sure where to start...but if you want photos, I don't have any just yet.

I have been interested in alternative fuels for quite some time but not really done anything about it. I recently picked up an '84 Cadillac Eldorado Biarritz from an estate auction, one owner 123K and belonged to fella' who ran a very reputable auto repair business. Well, with camping, the dogs and three kids, it didn't take long to figure out the Cadi just wasn't gonna' have a permanent home here, so....

I traded it straight across for an '86 Suburban, 6.2, High Sierra. It's a bit beat up, and has a few issues that I'll do some searching on before I post. Runs great, the guy I got it from was an Army heavy equipment mechanic. It's a 9 passenger, rear air, 2wd and it's PURPLE. So there's my sign on name...lol...

Glad to have found the site, I had been heavily involved in Datsun's for a couple of years recently, and Saab 900's for many years before that. I'm a decent mechanic, and I look forward to figuring out all the diesel doohickeys.

The truck has a BIODIESEL sticker on the back, I think it's one of the Sequential stickers. I'm not sure if it will currently run on anything other than #2 at the moment, but I have a stack of receipts in the truck for a tranny rebuild, injector pump rebuild and the engine replacement (at some distant point in the past).

Kids and I tore the headliner down for recovering, and generally soaked and cleaned most of the interior. It cleaned up well, but will need a few trim bits to be complete.

The passenger side valve cover seal is pretty much gone, and it's been gone for some time. The control arm bushings (and a bunch of others) are rotten from being oil soaked, I have an appointment to have a bunch of front end work done this Friday, and intend to have the valve covers resealed before that happens. I have no time to do it myself, so I'm stuck throwing money at it (which is in short supply these days). The tranny seems to hesitate on the downshift, but if I manually let off the throttle it will switch gears. Sticks in 2nd now and then and really howls 'til you let off and let it shift. Needs shocks and barn door seals, but otherwise it looks to be a pretty good trade. I go through about 6-10 cars a year, but I plan to keep this one for some time. It took me a long time to find one that I could afford. I'd like to get several years out of it, which means doing it right and saving to have it done if I can't do it myself.

I'll get photos up as soon as my photographer wife deems this truck worthy of her camera...:D

First off

WELCOME TO TDP :D:D:D

Good to see more folks fixing up the older rigs.

Where abouts in Oregon are you?? Meeeee too, live over by Newberg.

The good folks here at this site are always willing and able to help.

Good to have you on board


Robyn

Hiya Robyn! I'm just a few miles north of Eugene.

Paid a visit to OFI (Oregon Fuel Injection) today and had the valve covers and intake gasket repaired. In the process the fuel filter mounting started leaking badly. :(

I'm on a search now for fuel filter options, I drove it to my second job with a 30 micron inline fuel filter jimmy-rigged on top of the intake. It runs fine, but I don't want to risk having to a pump rebuild due to garbage getting in there. I'm only driving it about 30 miles a day, but I'm nervous about driving it like it is.

End of the week, I'll have pretty much the whole front end rebuilt and then I can start picking at the little stuff.

I'll do some searching here for fuel filter options, apparently the original 6.2 mount is NLA?

Pictures soon too, I hope. My wife keeps getting photo jobs and her 'SIM card is full'...lol...

Racor # 230R2
This is a great filter with a spin on element and a see through water bowl.
Better filter too.

You will need to make a mounting bracket, but thats a snap. Run the fuel lines to and from the filter and your set.

The Racor filter can be mounted where the existing filter fastens to the firewall.
You can make a little adapter plate to allow the filter to use the holes that are already in the firewall, or if you dont mind a little work, remove the air vent grille cover and then drill new holes in the firewall to allow the filter to bolt directly up.

You will not have the connections to the original water in fuel light or fuel heater but this is not an issue.

You can see the fuel bowl whenever you pop the hood to check the oil (Every fuel fill up)

Robyn

Thanks Robyn! I've been looking at a reman'd Racor 490R, still trying to determine what the actual fuel flow needs are for the 6.2. I've got a GM service manual coming for an '86 Suburban, but I'm not sure how much of the 6.2 it will cover.

My barn door seals and shocks arrived yesterday. :)

Just got a call from Les Schwab about the front end control arm bushings. The truck is an '86 2wd, and the ball joints he ordered are right, but the CAB's are too small. Is it possible the truck uses 1 ton bushings due to the heavier engine? Rockauto.com lists the same bushings for diesel and gas from about '76 to '90, but they are not right for this truck. Any ideas?

A few updates...

#1 Jiffy Lube put 15 quarts of oil in the engine and started it. Now the rear main is leaking, I'll have to pursue legal action here, I think. :(

#2 The new ball joints add to the confidence of driving the truck, but the CAB's are still shot. It's so badly out of alignment, the driver's front tire has worn into the steel bands and still has 11/32 of tread in the middle. Need to figure out what bushings I'll need. Doesn't seem like it should be that hard, it's a 2x.

#3 Torque converter bolts backed out and scared the heck out of me. I was able to have them tightened and lock-tited by O-F-I (Oregon Fuel Injection) and they gave the flywheel a clean bill of health when they fixed the loose bolts. Man, it sounded like the truck was going to come apart...

#4 Still on the quest for a cheap fuel filter. I plan to put another filter in line for now, the VW rabbit diesel can filter is 10 microns, and runs about $18, it also has a water drain.

Lovin' this truck more and more each time I drive it. :)

A DS4 equipped truck with a 6.5 needs a flow of around 35 Gallon an hour.

The 6.2 with the DB2 will not need near that much flow.

20 GPH is likely fine

I am using a Racor 230R2 on the DaHooooley truck.

Not too big to be handy to fit in easy.

Robyn

I have a set of new seals for the rear doors, but I'm not sure I understand how to adjust the door in the opening. The driver's side door is definitely not in the opening 'squarely'. There is a much larger gap at the top than at the bottom.

I'll do a little searching here, but the only adjustment I see is front to back, not left to right...

Sounds like time for hinge pins or hinges (yours are bolt-on). They wear out over time, and probably a long time ago in your case (and mine). Hinges, pins, striker bolts and latches are not uncommon items. LMC Truck should have them.

Been slowly correcting the little stuff wrong with this truck. Got all new dash bulbs in, and what a difference that makes. Ordered new door switches and strikers from RockAuto and now I've actually got a light that comes on when you open the door, and a door that doesn't constantly rattle when you're driving.

So, here's the issue I just found: There is water coming in the front section of the cab when the truck is parked. It usually sits in a level driveway a couple of days at a time. It hasn't rained hard here but the front floorboards, on the driver's side especially, are wet. It looks like it's dripping down about midway (front to back) on both kick panels ahead of the front doors. Is this a common problem? Is it just a poor seal/rusted lip on the windshield, or is there a vent or something that gets full of crud and rusts or overflows? The windshield is nearly new, but I know the lower flange corners were a GM problem area.

I am planning to reinstall the headliner, but as any PNW'r knows, if it's damp inside it'll just fall down again.

Thanks for any advice, I will eventually get some photos up :)

Still no pics, I know, that's lame.

Swapped in a new T-stat last week, and now the temp gauge is all over the place. The old thermostat was stuck open. It was running right around 190-200F when it was working properly.

So a couple of questions on what I might have done wrong. I drained the coolant from the petcock on the rad until is was below the level of the thermostat. Pulled the housing off, replaced the t-stat and gasket. Put it back together, and put the coolant I'd collected from the rad back in. I also added about 2 additional quarts of 50/50 to top off the radiator.

A couple of days ago, I noticed the burp tank was about 3/4 full (it had been just below the COLD line), so I drained that tank thinking I might have overfilled it on reassembly. I was thinking it was probably the 2 quarts extra I'd added.

Today, it ran up to nearly 260 before I could shut it down. Once I did, I checked the upper rad hose and it was only warm. Opened up the rad cap and the rad was 2 quarts low. The coolant level was just above the sensor, and the burp tank was almost full.

In the cab, the truck warms up to about 190, then over a bit and you can see the new thermostat open. From there it's all over the place. No heat in the cab unless the truck is moving, which makes me think the heater core has air in it...

So, maybe I've got a head gasket going, but it sure doesn't run like it has any compression issues. It has never blown any sort of white smoke, or smelled of coolant at the exhaust. No drippy water crap at the pipes either. I think I must have just forgotten to burp something and have an air pocket in there somewhere.

Today I put a new rad cap on after rechecking for any leaks (had a small drip at the T-stat housing and on one heater hose), my thinking being the old one might be sucking air. Didn't seem to make a difference, although the system is holding pressure better. It spews way better once it warms up and you pop the cap.

Advice? I know with other rigs, I've usually run the car up to operating temp with the rad cap off after a new T-stat. I think I forgot to do that this time. Is that all I need to do? I'd sure like my heater back.

When the engine warms up, check the upper radiator hose, it should not be really hard, if it is, the situation is likely a leaking head gasket.

Hate to bring up such a nasty thought, buttttttttttt, this generally the cause.

With your surge tank overfilling itself and all, plus the temps going way up.

Here is how do diagnose the issue.

Drain the system down far enough to get the coolant crossover off.
Fill the ports in the heads up to the top with coolant.

Remove the waterpump/fan belt
Start the engine and observe the two coolant passages.

You will likely see bubbles coming up to the surface.

The side that has the bubbles is the troubled side.

What can happen with a leak thats not real bad "YET" is that with the failed T stat the air leaking into the cooling system cam flow to the top and then blow off the cap and escape.
With a good stat in place the air is trapped and then forces the cooolant to back down away from the top of the engine and up and out the overflow into the recovery tank.

Now this said, if you find bubbles, indicating a head/gasket leak, with an older rig, do both sides.

You will need to replace the head bolts when doing this as they are a one time use bolt.

Best deal is to use a set of 6.5 late style heads gaskets as they are better than the 6.2 gaskets.

Oh just a note here. With this type of leak, there is nothing short of new gaskets that will fix the issue. The stop leaks and coolant tabs will do little if anything to stop this sort of problem.

Good luck and keep us posted.

Robyn

Thanks Robyn.

After doing some more research, I am going to get another T-stat. I didn't boil this one before I put it in, and the upper rad hose never gets hard. It almost acts like the T-stat is physically blocked. Last night it ran up to 240 and then opened. If I run it like that, it's bound to bake something. Since I need to drain the system as far as the thermo housing anyway, I'll check the crossover/heads before I get too carried away.

The primary thing I've noticed while messing with this is that the cooling system has been severely neglected. It's really full of crap and the coolant is dirty. I plan to back flush it regardless, and then fill it with distilled water and coolant. I think all I've got here is Prestone. There are about 3 diesel shops right next to my house, plus a truck stop with a service department. Should I see if they have recovered 'big rig' coolant instead? Or just put some DCA4 in with the Prestone? Money's super tight after Christmas and I'm crossing my fingers it's not a head gasket.

Is it possible the water pump is involved here? It only seems to pump heat into the cab when it's moving (higher revs). Could the pump blades be thin/bent/missing due to neglect or cavitation? I've only diagnosed water pump failures by checking the weep hole, and this one's not dripping.

All right, got the truck backflushed and put the OE (Napa) 195*F thermostat back in. I filled it with distilled water and Detroit diesel's name brand coolant (not Dexcool). I also added a little jug of this stuff called K-Line, and now I have no more bubbles in the burp tank, the cap is holding pressure and the heater works great (once the t-stat opens). I ordered a Mr. Gasket Hi-Flow 180*F thermostat, because with a 50/50 coolant mix, the thermostat is closing at idle and starts blowing cold air into the cab. I figure I'd rather have a lower thermostat than run straight water.

Should I consider a 160*F Thermostat?

I just re-read this last post, and honestly, it sort of looks like I 'short-cutted' repairs on this truck. I'm an OK mechanic, but not a pro for sure, and I thought I should clarify what I actually did here...

- I put a prestone backflush kit in, on the hose from the head crossover pipe to the lower heater core input.
- Removed the t-stat and backflushed the system. Put the old t-stat in and backflushed it again. Past experience has shown that sometimes you'll get a couple of big chunks of stuff that will stop at the t-stat, this is why I used the junk one.
- Drained and refilled the system to the level of the heads.
- Took the t-stat housing off and filled the cross over pipe to where it was just dripping a little liquid
- Removed the water pump belt (per Robyn) and started the truck.
- Since I didn't remove the crossover, I used an LED flashlight and dental mirror to watch for bubbling by looking in the t-stat opening. I didn't see any bubbling.
- This led me to believe the problem was either the t-stat, t-stat housing, crossover gaskets, rad, heater core or hoses.
- I boiled my new t-stat a couple of times, put everything back together, refilled and brought the truck to operating temp (put the belts back on at this point too)
- With the new rad cap, I found the leak(s). Add to this my realization that this is not a 'closed' system and things began to make more sense.
- The rad was leaking just above the connection for the output from the heater core, the heater hoses were leaking at the heater core (both of them).
- Had to drain the system again about 1/2 way, replaced the heater hoses with new silicone hoses (from the truck stop nearby). Filled it back up and watched for leaks. This is where I found the rad leaking.
- At this point I decided to put the K-Seal in.
- My mixture is off a bit, and the truck now runs about 160* F, with a stock 195* F t-stat.

What it looks like, is the system was sucking air near the heater hose connection on the radiator, and possibly my first replacement t-stat was not opening at the correct temp. The sealer, as Robyn said, would probably not work on a head gasket problem, but I now have no cooling issues, so it did fix a leak somewhere (in the radiator). Add to this, my misunderstanding of the pressure required within the system, and I'd overfilled it on my first couple of attempts to replace the t-stat.

Took me about 4 tries to get it right, but it sure runs nice now, and the heater works like it should. This all started because of a stuck thermostat, so lesson learned, go over the manual BEFORE I start tearing into stuff. I realize this isn't the premium solution to a radiator leak, but funds are tight, and at least now I know it will probably need a rad in the future. Beats having to replace the head gaskets IMO.

Anyway, I didn't mean to make it appear that I'd tried to 'fix' a head gasket problem with a bottle of sealer. The biggest problem, really, was a not too observant mechanic. :rolleyes: