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-   -   Engine Questions for a Rookie (https://67-72chevytrucks.com/vboard/showthread.php?t=638511)

Litespeed54 08-05-2014 10:28 PM

Engine Questions for a Rookie
 
Gents,

I have a few questions for you from this rookie. I think I've solved the over heating problem that I was having last week. I replaced the radiator cap, thermostat, and reattached the lower radiator hose. Filled back up with fresh antifreeze and the coolant gauge stays just above cold. So that's good.

But I drove it tonight and once again, after awhile, it becomes sluggish. Almost like the brakes are being applied. I pulled in the garage and the motor seems awfully hot but the gauge doesn't show it. I know the gauge works because I saw it get high last week before my current repairs. Onto my questions.

I'm going to forward you several pictures, focusing on the valve covers. The driver side valve cover has one hole while the passenger side has two holes. The driver side has a hose going into it from the lower part of the carb. The passenger valve cover's front hole is open with nothing going into it. The rear hole has a hose coming out of it and going into the carb, above the flaps.

I've read some things about a PVC valve which I am not sure I have. I also don't know what should be in that don't hole on the passenger side valve cover. Any thoughts? Could that open hole be causing the sluggish problem?

Thanks!

RPBurris 08-05-2014 10:43 PM

Re: Engine Questions for a Rookie
 
The hose from your valve cover to the carb is indeed your Positive Crankcase ventilation (PCV) valve. Both sides usually do not have one. The other side can either have just a breather cap or fill cap but should definetly have something. Neither one of these should affect your performance. I would double check all of your fluids to make sure they are at the proper levels. Make sure you dont have water in your oil (it will be way over filled and milky). Its a little concerning in your post you said you reconnected your lower radiator hose. Did it blow off? Also assuming you are dealing with a small block. Stock gauges or aftermarket? A little more info can go a long way and pictures are worth something like 999 words. Good luck and welcome to the board!

Litespeed54 08-05-2014 10:58 PM

Re: Engine Questions for a Rookie
 
1 Attachment(s)
I am posting pics. I recently purchased this truck and for the first few weeks things were absolutely wonderful. Then, last week, after a 15 mile drive I pulled into the garage for lunch. Came back out and it dumped all coolant because the lower radiator hose popped off. I will also say that during that 15 mile trip home the truck started running a little rough but it honestly felt more like a bad tire. There was a wobble and it was sluggish (same thing that happened tonight). I reattached the hose with new clamps, replaced the radiator cap and thermostat. Until tonight it was fine and it definitely did not overheat. All gauges are stock. Truck has original engine with 79k miles.

I should also mention I checked the oil and it was clean. But I did have it changed just today. Blows a little smoke out the tailpipes but not much at all.

Litespeed54 08-05-2014 10:59 PM

Re: Engine Questions for a Rookie
 
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Another pic.

Litespeed54 08-05-2014 11:00 PM

Re: Engine Questions for a Rookie
 
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Pic 3

Litespeed54 08-05-2014 11:00 PM

Re: Engine Questions for a Rookie
 
1 Attachment(s)
Pic 4

Litespeed54 08-05-2014 11:01 PM

Re: Engine Questions for a Rookie
 
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This pic was taken a few weeks back. As you can see, it has an oil cap in the front hole of the passenger valve cover. I noticed it missing tonight which must mean the shop forgot to put it back in when I had the oil changed today.

Litespeed54 08-05-2014 11:02 PM

Re: Engine Questions for a Rookie
 
1 Attachment(s)
Thought I'd post a pic of the truck. It's a beauty!

tcrist 08-06-2014 12:48 AM

Re: Engine Questions for a Rookie
 
You might want to check the PCV to be sure it is not plugged. It is the item that is in the valve cover in post #4.

Remove it and see if you can blow thru it from the side that is in the valve cover. If not, or it is really hard to blow thru, you should replace it.

If it is clogged then it could be causing pressure and that could cause the oil filler cap to blow off if it is just a press in style.

engineer_gregh 08-06-2014 07:04 AM

Re: Engine Questions for a Rookie
 
Just as tcrist suggests; pull the PCV valve out and shake it, it should rattle. It looks as if there is no fuel filter between the fuel pump and the carb. If that is in fact the case and you are running fuel with ethanol then I would suspect rust, trash, etc. in the fuel. I found someone had installed a fuel filter just below my tank and it was causing some of the same symptoms you described. Very frustrating playing hide and seek with fuel filters:-)

mechanicalman 08-06-2014 06:15 PM

Re: Engine Questions for a Rookie
 
Driver's side PCV, check.
Passenger side filtered air inlet for the PCV to work, check.
Passenger side hole for oil fill plug, looks funky not sure though cause the pic is dark. Usually a rubber oil fill plug goes there without a grommet, but that looks like a grommet. You should be able to get a replacement oil fill plug at the "help" section of the parts store. If the valve covers are correct, you will need to remove what appears to be a grommet. You could maybe just put a push-in breather and use it for an oil fill, if it fits.

Don't see how this could affect performance.

mechanicalman 08-06-2014 06:16 PM

Re: Engine Questions for a Rookie
 
Good call.

Litespeed54 08-07-2014 07:38 PM

Re: Engine Questions for a Rookie
 
You guys have me wondering if I didn't put Ethanol in it. Let me describe my further issues. The night I changed out the thermostat and radiator cap, and reattached the radiator hose, I went and filled up with gas (premium) and drove home. When I pulled in the driveway and stopped, gas was pouring out underneath the cab. I checked underneath and it was coming from the rubber fuel hoses just under the tank. It leaked several gallons, then stopped. And hasn't leaked since. Does this help? Also, should I install a fuel filter between the carb and the fuel pump? Lastly, I check the PVC valve and it does rattle and it does let plenty of air through it. Seems fine. I really appreciate the advice!

PanelDeland 08-07-2014 09:56 PM

Re: Engine Questions for a Rookie
 
Check the hose where you saw the leak.It may either be a bad rubber hose or maybe a overflow condition from the vent.If the hose is bad and sucking air,it could cause a stumble.

davepl 08-07-2014 10:22 PM

Re: Engine Questions for a Rookie
 
Quote:

Originally Posted by engineer_gregh (Post 6790497)
It looks as if there is no fuel filter between the fuel pump and the carb.

Q-Jets have the filter right in the inlet housing. Some people like an extra filter but I've never felt the need, and the factory didn't appear to either. I'd never cut a hard line to put a rubber hoses filter into it, at least.

If you had, for example, a 396/375 that used a Holley then the factory added a steel case filter with proper steel fittings.

davepl 08-07-2014 10:24 PM

Re: Engine Questions for a Rookie
 
You mean E85? It'd run pretty lean, and hot, as I think it takes 4X as much ethanol for the same amount of 'fuel' as gasoline. I'd actually be surprised if it ran.

Litespeed54 08-08-2014 12:03 PM

Re: Engine Questions for a Rookie
 
No, not E85. Just a blend.


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