Fuses and carb questions?

[blazer88]

I have an 84 blazer, it has a 350 crate motor, and all the parts on it look to me to be original parts. In the enormous engine bay there is a 30amp fuse in an exposed holder(by exposed I mean not covered and open to the elements, rain) it is you standard size 30amp fuse. I have a covered 30amp gigantic fuse, one of the really big ones, left over from my flexalite fan install on a different vehicle, they are both 30amp fuses I assume they would both carry the the same amperage and power. the one currently installed looks to be eight gauge wire and the new one with the large fuse looks to be a ten gauge.

The other question is it is a stock carb, but 50% of the time it does not idle, it will fire up then start to idle really rough and idle will slow and then die, if i keep the idle up and put it into gear and drive off the problem will go away quickly, it usually does it on cold mornings, I assume the mixture is not set correct, and sometimes from a stoplight or from a stand still it feels like it wants to bog, should i just take it to my mechanic and have him adjust or rebiuld the carb?

Sorry for the two part question but you guys are always good.

 

[lectric80]

There is no stock 30 amp fuse under the hood of a Blazer, at least none I have ever seen. But, to answer your question, it shouldn't make any difference replacing the exposed fuse with a new one. Now, I want to know what it runs to, as it sounds like either a fuse for an amp, or a fuse that was put into place when a PO replaced the fusible link. If it is replacing the fusible link, you should really get back to using the fusible link for supplying main power to the truck.

As to your second question, have you verified the choke is opening? How soon after starting does the rough idle start?

 

[blazer88]

Fusible link

It is a fuse replacing a fusible link. It is to the starter, and it is done by the previous owner, or the one before him I'm not sure. I would run the wire back to the fusible link, but it is one of the biggest cluster***** of wires that I have ever seen. I have slowly been pulling out old wires that are no longer running anything. 2 owners ago had a big stereo, dvd, screens, and all the junk, an alarm, and I have slowly been pulling those out.

I have not checked to see if the choke is opening, it only does it part of the time. Half the time it fires up no problem.

 

[lectric80]

Gotta love PO's.

 

[blazer88]

PO's are great

Well it died on me in the school parking lot, took better part of five minutes to get it started again. But it was falling on its face in first gear. So I talked to my local autozone and pepboys, and both people pointed towards the transmission, and some sort of sensor or switch. I took it to a local transmission shop to have it looked at. The shop owner also said it sounded like something tranny related. We will see if anything turns up, if not it is back to the witch hunt. Will keep posted.

 

[lectric80]

An 84 Blazer shouldn't have any sensors in the trans. At most it would have a 700r4 tranny, not anything electronic in those years. Unless it is a vacuum leak causing it not to shift, there isn't really anything else. If it is a vacuum leak, it would be a very loud leak since it is a large line to the th350.

 

[Fordum]

<Gotta love PO's.>
Hey, I resemble that remark<G>.
My old truck before this one, I installed a dual battery system.
The stock battery, stayed where it was, and I put in a heavy plate high current one that would really spin my starter.
Which was all it had to do.
On the other side of the engine compartment, was the mount for a second battery which was used when the diesel option was ordered.
Since I had gas, that mount went unused.
I put in a 90 plate long term battery in that mount.
When I got in and turned the key, all that battery had to have was enough power to to spin the starter.
The long term battery powered everything else including starting solenoid.

I gave it to my friend, years later. He got sick, and asked if he could give it to a friend of his who had taken care of him as he was dying.
I said sure.
About 3 months later, I got this phone call from the guy. He told me that they had put my old truck in their shop to fix a tie rod end.
He said when went to start it , it seemed to have a dead battery.
But, they could not jump it off, and he wanted to know had I instilled equipment that prevented it from cranking?
I rode over to their camp.
When I walked up, I noticed that only one battery was under the hood.
I asked where the other battery was.
They informed me that some of their friends had borrowed the "spare" battery, since they would not need it.
Since the starter solenoid ran off that one, it never turned over.

J.

 

[blazer88]

sensor/cable

It is the 700r4, it shifts fine, but in first gear it stumbles and falls flat, and died on me today. I don't remember if the said it was a sensor or a cable of a sort, but it was described to me as possibly being in between second and first, not quite in either. Have it at a tranny shop now.

Speaking of PO's

The guy I got it from installed the 4.88 gears, I am not sure what gears were in it before the 4.88's. I would assume the stock 3.73's, but who in their right mind would do 3.73's with a 4inch suspension lift and a 2inch body lift and 37's?

And there is a second spot for a battery, it is on the passenger side right now, with a second spot on the driver side. I only see a ground cable on that side nothing else, there is a ton of wires from previous stereo/dvd/alarms. When I bought it, it had one battery. I have since replaced the battery, with an Optima Yellow Top, and installed a JEGS 140 amp 1 wire alternator, the old one crapped out on me. I've done alternators before and I am pretty confident that I did not mess something up.

Previous owner did have an electric fuel pump installed, but was going to move it to the frame, before he sold it to me, made noises in the spot he had it, but ended up replacing it with the mechanical fuel pump, a new one too.

When it died earlier today, it took quite a few minutes to get it started. Cranked over fine but stunk to high heaven of gasoline. Finally did get it started and into a parking spot. Drove home fine, besides being lame in first. I thought fuel issues. But was pointed in a different direction. I planned on putting a new fuel filter in, but was talked out of it. Can't really hurt to put a new one in. Just typing out loud here now, but

Could it be the fuel pump?
The fuel filter?
The carb?
Could it be the distributor? Has a hypertech street/strip module.

Sorry for the essay, just trying to type it all out. All the repairs has me down and out. Will join the website this week after all this help.

 

[lectric80]

Is there a pressure regulator on the fuel line? If not it could be overpowering the needles and flooding the engine out. You need very little pressure for a carb setup, and most electrics will need a pressure regulator.

 

[blazer88]

Pressure Regulator

I do not know if there is a pressure regulator on the fuel lines. It is at a shop right now so I can't hop under it and look. It is back to the mechanical fuel pump, no more electric.