Hi all,

I've moved up in the world to a '98 Jimmy for myself and a '00 Blazer for my wife. The Jimmy I rescued from someone here in Graham who had driven it a short time until the intake manifold gaskets gave out. I bought it and towed it over to my house a couple miles away. I replaced the gaskets with the good Fel-Pro gaskets. I also replaced the fuel line o-rings, water pump, fan clutch and thermostat. I drained the old, coolant-laden oil and the remainder of the Dex-cool. I replaced the oil filter and refilled the engine with clean oil. I ran it for a while and then ran a can of SeaFoam through it and drove it hard. The SeaFoam cleaned out tons of gunk and carbon.

The Jimmy runs and drives very well now. Is there anything else I should do? I'm planning on running it a little bit more and then changing the oil and filter again. Should I put some SeaFoam in the oil before I drain it and replace it?

Thanks for all your help. Because of the great info on this forum I was able to plan ahead and replace the thermostat, water pump and fan clutch when I did the gaskets.

 

Sounds like you're on the right track. I would do a good flush of the cooling system as well.

 

When I got my blazer I changed all the fluids, coolant, oil, both diffs, transfer case, brake fuild, power steering fluid just so I know whern they were changed & off to a good start.
I also had the trans back flushed to remove all the fluid that the converter holds inside & the cooling system power flushed.
I did a sea foam treatment to the engine, gas tank & brake booster as well.

 

Forgot to mention, you might want to shake down your front end. These trucks like to eat hubs and ball joints. Might want to do a tune up and clean the maf and egr just for good measure.

 

X2 on what cat said... plus look for vacuum leaks (brake cleaner sprayed over the lines, if the idle changes, you found a leak!) Vacuum is very important to these vehicles.
Stock front end should be good if you have stock rims & no lift. But yeah CV joints & ball joints are an or can be an issue.

 

As near as I can tell this truck is stock. I'll check out the front end once I'm done with the engine. I rebuilt the front end in both my old '94 Blazer and my '93 Sonoma pick up so I'm no stranger to doing that particular job, should it be needed.

The previous owner replaced most of the vacuum lines and flushed out the cooling system shortly before I bought it. I got as much of the old coolant out as possible when I removed the water pump.

I'm mostly concerned with getting any residual sludge out of the engine for right now. I drove the Jimmy around this afternoon and the oil pressure was higher than I would like which makes me worry about the bearings. Pressure is about 30psi at idle but holds pretty steady about 55psi while driving. My wife's '00 Blazer idles around 30psi and cruises just under 40psi, all pressures according to the dash gauge in each vehicle.

Thanks again for all of your information. After years of driving and fixing first gen S10s it's fun to have a new challenge and new things to learn.

 

I wouldnt go so far as to say they eat hubs and ball joints. In 240k hard miles, I've replaced one ball joint and both hubs one time each.

 

Here's an update:

I poured half a can of Seafoam in with the oil and drove the Jimmy into Tacoma tonight. By the time I got home the oil pressure (according to the dash gauge) was around 25psi at idle and around 40psi while cruising. This gives me hope that after draining the oil and changing the filter that the motor will be in pretty good shape. I'm going to run Pennzoil 5W-30 and some Lucas Oil Stabilizer after the change. We'll see what happens next.

My next project will be replacing the blend door actuator because the Jimmy puts out heat no matter what the temperature is set to.

 

Lucas oil stabilizer is pretty much nothing more than a thickener for your oil. I've never heard of oil needing to be stabilized. Ever. Have you seen the stuff? It's like 180 wt oil or something crazy. If you want thicker oil, buy a heavier weight. Try 15w-40. That Lucas junk is just that. Junk.

 

I'd have bought a thicker oil if I didn't already have a jug of 5W-30 sitting around waiting to be used. If the thicker oil helps then I'll use thicker oil on the next oil change.