Engine Doesn’t Like Starting When Hot

• Apr 2, 2023

• #1

CarterDawson

Junior Member

Joined

Mar 6, 2023

Posts

19

Reaction score

16

Location

WA

First Name

Carter

Truck Year

1975

Truck Model

K-20

Engine Size

350

81 K-1500
It’s got a 305 with Edelbrock performer intake, AVS 2 Carb and headers. I bought the truck this way. I wouldn’t waste my money on the 305. Oh well. When I drive the truck enough for it to get hot, and turn it off, it doesn’t like to start. It rolls over real slow, for about 7 seconds. Then speeds up and fires up. Like it’s flooded. But after is cools for 5 mins it fires up immediately. Is the truck overcarbed? Should I put smaller jets and rods in? I can’t figure it out. Just set the float level today. It’s been doing this since I bought the truck. Thanks.

 

• Apr 2, 2023

• #2

squaredeal91

Full Access Member

Joined

Mar 10, 2023

Posts

1,783

Reaction score

3,134

Location

Cave junction Oregon

First Name

Greg bush

Truck Year

1991 SB

Truck Model

K30

Engine Size

5.9 Cummins 12 valve

I'm not big on edelbrock carbs but they do run okay. even the 1406 can be over jetted for a 305 and some 350s. Does it seem like it's vapor locking? I've had similar issues in the past.

 

• Apr 2, 2023

• #3

squaredeal91

Full Access Member

Joined

Mar 10, 2023

Posts

1,783

Reaction score

3,134

Location

Cave junction Oregon

First Name

Greg bush

Truck Year

1991 SB

Truck Model

K30

Engine Size

5.9 Cummins 12 valve

Check Timing, sounds like it could be too advanced to start warm/hot

 

• Apr 2, 2023

• #4

PrairieDrifter

Full Access Member

Joined

Dec 28, 2014

Posts

3,447

Reaction score

4,548

Location

North Dakota

First Name

Mason

Truck Year

84,79,77,70,48

Truck Model

Suburban k10, bonanza k10, c30 C&C, c10, gmc 1/2ton

Engine Size

350, 350, 350, 350, 350

Timing, or the starter is getting heat soaked.

 

• Apr 2, 2023

• #5

CarterDawson

Junior Member

Joined

Mar 6, 2023

Posts

19

Reaction score

16

Location

WA

First Name

Carter

Truck Year

1975

Truck Model

K-20

Engine Size

350

squaredeal91 said:

Check Timing, sounds like it could be too advanced to start warm/hot

Click to expand...

PrairieDrifter said:

Timing, or the starter is getting heat soaked.

Click to expand...

Ok. Thanks. I’ll set timing tomorrow.

 

• Apr 3, 2023

• #6

CarterDawson

Junior Member

Joined

Mar 6, 2023

Posts

19

Reaction score

16

Location

WA

First Name

Carter

Truck Year

1975

Truck Model

K-20

Engine Size

350

squaredeal91 said:

I'm not big on edelbrock carbs but they do run okay. even the 1406 can be over jetted for a 305 and some 350s. Does it seem like it's vapor locking? I've had similar issues in the past.

Click to expand...

My initial thought was vapor lock. But I don’t think that’s the case anymore. After going through the whole fuel system there doesn’t seem to be any vulnerable spots.

 

• Apr 3, 2023

• #7

waterpirate

Full Access Member

Joined

Jan 2, 2019

Posts

825

Reaction score

1,846

Location

delaware

First Name

Eric

Truck Year

1987

Truck Model

v10

Engine Size

5.7 tbi

My timing was off and the truck acted like yours.
Eric

 

• Apr 3, 2023

• #8

QBuff02

I like Big Blocks and I cannot lie

Supporting Member

Joined

Feb 28, 2017

Posts

867

Reaction score

1,591

Location

Central IL

First Name

Quincy

Truck Year

1982

Truck Model

K30

Engine Size

454

Edelbrock carb=Vapor locking. Put a phenolic spacer between carb and intake. It's boiling the gas out of the carb when it heat soaks. and check the timing as well.

 

• Apr 3, 2023

• #9

Rickf

Full Access Member

Joined

Jul 29, 2017

Posts

467

Reaction score

556

Location

Grafton NH

First Name

Rick

Truck Year

1974, 1954 & a 1937

Truck Model

K20

Engine Size

350

If the starter doesn't have a heat shield, then you might try adding one.

 

• Apr 3, 2023

• #10

scrap--metal

Full Access Member

Joined

Sep 15, 2021

Posts

678

Reaction score

1,266

Location

MN

First Name

Calvin

Truck Year

'85, '81

Truck Model

K10, K20

Engine Size

305, 350

All the suggestions above are good, and any one of them could be a possibility. Does your truck have headers?

PrairieDrifter said:

starter is getting heat soaked.

Click to expand...

^ This was happening to my Camaro last summer. Would start great cold, but hot it seemed like the timing was too advanced to start. In reality the old started was too tired to turn over well while hot. Headers without a heat shield get that starter HOT. A new starter solved the issue. No heat shield necessary.

 

• Apr 3, 2023

• #11

CarterDawson

Junior Member

Joined

Mar 6, 2023

Posts

19

Reaction score

16

Location

WA

First Name

Carter

Truck Year

1975

Truck Model

K-20

Engine Size

350

QBuff02 said:

Edelbrock carb=Vapor locking. Put a phenolic spacer between carb and intake. It's boiling the gas out of the carb when it heat soaks. and check the timing as well.

Click to expand...

Yes. I added a phenolic spacer. I didn’t notice it helping at all.

 

• Apr 4, 2023

• #12

CarterDawson

Junior Member

Joined

Mar 6, 2023

Posts

19

Reaction score

16

Location

WA

First Name

Carter

Truck Year

1975

Truck Model

K-20

Engine Size

350

I set the timing by ear and it runs like a top! Thank you very much.

 

• Apr 4, 2023

• #13

squaredeal91

Full Access Member

Joined

Mar 10, 2023

Posts

1,783

Reaction score

3,134

Location

Cave junction Oregon

First Name

Greg bush

Truck Year

1991 SB

Truck Model

K30

Engine Size

5.9 Cummins 12 valve

Right on! Glad it worked out

 

• Apr 5, 2023

• #14

CarterDawson

Junior Member

Joined

Mar 6, 2023

Posts

19

Reaction score

16

Location

WA

First Name

Carter

Truck Year

1975

Truck Model

K-20

Engine Size

350

Thank you guys.