Look for vacuum leaks.
CK5
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Fun Driver
- Thread starter ChrisAwesome
- Start date
Smurf is currently in my hands. Check its past record here:
https://ck5.com/forums/builds/74-k5-build-smurf.112/
ChrisAwesome
1/2 ton status
How do I check for vacuum leaks? How do vacuum leaks affect the driving? What are the symptoms of vacuum leaks?
Vacuum leaks will let air in after the fuel is mixed. This will affect the mixture and change how it runs, usually with a loss of power. You want to look at all the little hoses coming off the throttle body and intake manifold.( I think you have TBI, I haven't looked back through all the posts. Same type of hoses on a carb too.) There are vacuum hoses going to all sorts of things, distributor, emissions, auto trans, brake booster, heater controls etc. Look for unhooked hoses, cracked hoses, that type of thing. Look to see that the TBI is bolted down tight and the base gasket is in decent shape. Not sure what trans you have but a th350 or th400 has a vacuum line going to it and this would also affect shift characteristics is there is a leak.
He has a 700r4 now.
Hi Chris
Can you describe what happened when you lost power?
Can you post a video of how it runs now.
It must be something loose.
For finding vacuum leaks first look at the obvious, things loose or off like the hose you found.
If you can't find anything you get brake cleaner or carb cleaner and you spray around the throttle body while the engine is running and see if it idles higher then move around to hoses.
When you hear the engine idle faster you found a leak.
If this happened instantly you have something disconnected.
Might also be a spark plug wire.
ChrisAwesome
1/2 ton status
Haven't been here in a while. I changed air filter, old one was dirty and had some pine cones in it. That probably cut the air supply off completely. Anyway, that's replaced now.
What's the best air pressure for pavement driving? My tires are 37x13.50 Toyo MT's. Whole Blazer is probably around 7000 lbs of total weight as it is right now.
What's the best air pressure for pavement driving? My tires are 37x13.50 Toyo MT's. Whole Blazer is probably around 7000 lbs of total weight as it is right now.
The tire sidewall will give you a better idea of range. What load rating are you at?
just winging it I’d say somewhere in the 40s for street pressure. But the tire will tell you what it wants based on how it fills out.
just winging it I’d say somewhere in the 40s for street pressure. But the tire will tell you what it wants based on how it fills out.
For that weight somewhere in the 40-60 psi range will work fine. Lower will ride nice but be more "squishy" in turns and get worse mileage. Higher will ride a bit stiffer but rolling resistance will be reduced. If you run on long highway trips with them lower they will also build more heat in the tire.
I always use the scientific way.
Draw a chalk line across the tread and drive back and forth a couple of times, the line should wear evenly.
If it wears more in the middle it's overinflated, if it wears the edges it underinflated.
I would go with a hint overinflated for better mileage.
By the way if I remember correctly it had a K&N reusable filter, you clean it and re-oil it.
ChrisAwesome
1/2 ton status
I topped up all of the wheels from 30psi to Approx 37-38 psi. It took me 45 min with small viair compressor... Where do I find actual pressure recommendation for those tires?
There isn't really a place to get a value. It depends a lot the weight of the truck. Your pressure sounds good. Many will use chalk across the tread and move it a short distance and look for the chalk wearing off. Correct pressure will wear off the tread evenly side to side. Too much pressure will have it wipe the chalk off the center, too little and it will wipe off the edges first.
