Heater hose re-route around the TBI? Should I or should I not?

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Coal creek Chris

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How important is it for coolant from the heater hose to pass through the TBI on an 89 V3500 with 7.4L engine? While doing another project, I noticed that the heater hose connection at the back of the TBI is loose and looks like the connector plastic is partially broken. This is a heater hose with a metal end that snaps into a fitting on the TBI. The other end of the heater hose is rubber and attaches to heater core with a clamp. The fitting is the bigger one in the center of the photo, the other two are fuel. Looks like one of those projects that could turn into a mess if I try to replace the fitting that threads into the TBI, so I was wondering about bypassing it to the small coolant hose on the front of the TBI. But only if it won't cause other big problems or if it is essential that the TBI has coolant flow through it . Any thoughts and suggestions would be great. I live in a place with winter if that matters for this question. Thanks.

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bucket

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I bypassed mine. It still runs great in cold weather without the coolant plumbed in.

Edit: Forgot I had a picture. I found a pre-formed heater hose and used it to bypass the TBI heater. The hose goes from the heater core, straight to the intake. It's a newer body truck, a square body truck has less demanding heater hose requirements.

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Coal creek Chris

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Chris
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1989
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Thanks. I'll probably go that route then because the replacement fitting on the TBI seems like it is not available at parts stores.
 

bucket

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Thanks. I'll probably go that route then because the replacement fitting on the TBI seems like it is not available at parts stores.

They are usually found in the Dorman or "Help!" isle at the chain stores.
 

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