Big Block Bypass Hose - The 1947 - Present Chevrolet & GMC Truck Message Board Network

tucsonjwt · 07-12-2011, 11:38 AM

Does anybody use a molded bypass hose on their 454? I have an 83 C20 and don't like using a 3/4" heater hose as a bypass hose because it kinks and does not make a smooth transition. Most catalogs specify just a piece of 3/4" hose. Does anyone have a GM part number on an OEM bypass hose and/or a picture of one? Like so many things on our old trucks, finding these small parts is a real challenge.

kelsfine69 · 07-12-2011, 12:29 PM

I was looking at getting one of these but havet fiqured out which one I need yet.

http://www.coolflex.com/cfm/store.cf...t=3&mode=parts

tucsonjwt · 07-12-2011, 12:38 PM

I am ordering the LMC one since I cannot find one locally, and the local Chevy dealer is no help (as usual). None of the pics I see online look like they are a good fit, but I will try the LMC one for $12.70 delivered and let you know how it works out. I think I will have to cut it, but at least then I can post an actual measurement and pic that looks correct for a big block. I see some bypass hoses for earlier big block Corvettes, but nothing into the 80s.

Grande Rojo · 07-12-2011, 01:06 PM

I had the same problem with mine. I ended up using a 45* npt elbow. Works great. I can post a picture later.

Keith Seymore · 07-12-2011, 03:38 PM

Quote:

Originally Posted by tucsonjwt

I see some bypass hoses for earlier big block Corvettes, but nothing into the 80s.

Should all be the same; I typically use Corvette stuff for the big block in my Chevelle.

K

tucsonjwt · 07-12-2011, 04:12 PM

I'd like to see that NPT pic. Is the elbow threaded on both ends, so you thread one end into the water pump and attach the hose to the other threaded end of the nipple?

baclay9 · 07-12-2011, 05:14 PM

I'd like to see something better too, my hose is kinked a little and it is driving me crazy.

justpball · 07-12-2011, 06:07 PM

I blocked mine off with a plug, it still stays cool, so what is it's purpose?
Posted via Mobile Device

Grande Rojo · 07-12-2011, 07:24 PM

It's a 45* street elbow male end screws into intake manifold and the female end faces down with a threaded nipple for the short hose to the pump. Only cost a few bucks and no kinks. I'm sure it could be smoothed out a little more and painted nice. (I tried posting a picture but my Damn not so smart phone wont let me. I'll try from my home 'puter)
Posted via Mobile Device

raceman6135 · 07-12-2011, 07:49 PM

Try these molded hoses:

Dayco #70647
Gates #20618
Goodyear #63394

They should all look like this:

tucsonjwt · 07-12-2011, 08:12 PM

Thanks for the part numbers. All of them show that they do not fit my 83 C20 when I look them up online, but like Keith says I think they should work anyway. I am interested to see what the LMC hose looks like when I get it. I bet even the OEM stock hoses require some cutting to get it to fit. The similar GM OEM short hose from the air cleaner to the valve cover vent hose I paid big $$ for (and looked similar) required modification when I got it.

Metalspatter · 07-12-2011, 09:24 PM

I have replaced mine twice now from pulling the intake so many times. Both times I just look through the NAPA hose wall, pick one with the correct bend molded into it, and cut the rest away. Works perfectly and costs only a couple dollars.

KQQL IT · 07-12-2011, 10:49 PM

I used a piece of blue silicone hose. Bent without kinking.
Posted via Mobile Device

78maliburat · 07-13-2011, 12:21 AM

MINES A TALL DECK I USED STRAIGHT HOSE

**Corts60** · 07-13-2011, 12:37 AM

Just go to your local parts store and ask to check out the molded hoses. Pick the one that has the right degree elbow (even if it is way too long) take it home and cut it to fit.

maskale · 07-13-2011, 12:46 AM

Quote:

Originally Posted by Metalspatter

I have replaced mine twice now from pulling the intake so many times. Both times I just look through the NAPA hose wall, pick one with the correct bend molded into it, and cut the rest away. Works perfectly and costs only a couple dollars.

Yep, thats what I have done.

tucsonjwt · 07-20-2011, 12:25 AM

I just got my long awaited correct bypass hose from LMC. Looks like I spent $13 for nothing - somebody just cut a length of 3/4" heater hose off a reel and sent it to me. Probably not worth my additional shipping cost back to LMC + my original $13 to prove a point, but what a disappointment from this vendor.
Yet another item to add to my list of minor irritations relating to people no longer taking any pride in their work. I wouldn't mind if they didn't cost me money. Looks like I will have to try one of those "incorrect" correct bypass hoses mentioned previously.

maskale · 07-20-2011, 07:56 AM

that sucks, I would send them some hate mail, make them refund ur money and keep the hose.

tucsonjwt · 07-20-2011, 02:12 PM

LMC says they will refund the purchase price including shipping, and don't need the 6" piece of heater hose returned to them. It took about 20 minutes of holding/talking with customer service/check with supervisor, etc. I was told another customer already complained about getting a 6" piece of hose instead of a molded hose. I don't know why they are still allowing customers to order this part. I wonder when/if I see the credit show up in my account?
I ordered the two water pump fittings and a molded bypass hose from Corvette Central based on the way the parts look in their online catalog. I am anxious to see what I get for my $38, and if my truck runs faster (like a Corvette) after install.

maskale · 07-20-2011, 10:07 PM

Like I said I went to napa and picked a hose that looked like it will work. I bought it several weeks ago, installed it tonight.

Advice, cut just a little at a time, and actually put it on to test the fit vs holding it next to where it goes, I cut mine borderline to short, but it will work for now

cost 12.99 IIRC, part number shown on hose

tucsonjwt · 07-20-2011, 10:30 PM

Thanks for the tip. I will have to take a picture into the local NAPA store to show them what a bypass hose looks like, since they claim they don't have any and their online store says they have it. Looks like this one has multiple bend angle options for maximum flexibility.

https://www.napaonline.com/Catalog/C...267473288&An=0

tucsonjwt · 07-25-2011, 05:14 PM

I got my Corvette Central bypass hose and two water pump fittings today. I only took 4 days over the weekend to get the parts via USPS priority mail. The 20 degree angle water pump fitting is supposed to be for 59-62 Corvette, the other fitting is supposed to be for 65-74 big block engines, and the bypass hose is supposed to be for 66-67 big block 427 engines. So, I guess my 83 big block 454 covers many generations of Corvettes. $38 for the 3 parts, including shipping, and the Delco water pump was only $34.

I hope these parts do the job. Pics.

tucsonjwt · 07-26-2011, 03:31 PM

Installed Corvette water pump fittings and bypass hose with no kink. I cut about 1" off both ends of the hose.

maskale · 07-26-2011, 03:58 PM

good ya got it worked out.

07-12-2011, 11:38 AM	#1
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Big Block Bypass Hose Does anybody use a molded bypass hose on their 454? I have an 83 C20 and don't like using a 3/4" heater hose as a bypass hose because it kinks and does not make a smooth transition. Most catalogs specify just a piece of 3/4" hose. Does anyone have a GM part number on an OEM bypass hose and/or a picture of one? Like so many things on our old trucks, finding these small parts is a real challenge. Attached Images

07-12-2011, 12:38 PM	#3
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose I am ordering the LMC one since I cannot find one locally, and the local Chevy dealer is no help (as usual). None of the pics I see online look like they are a good fit, but I will try the LMC one for $12.70 delivered and let you know how it works out. I think I will have to cut it, but at least then I can post an actual measurement and pic that looks correct for a big block. I see some bypass hoses for earlier big block Corvettes, but nothing into the 80s.

07-12-2011, 01:06 PM	#4
Grande Rojo paper or plastic? Join Date: Nov 2002 Location: SW Missouri Posts: 671	Re: Big Block Bypass Hose I had the same problem with mine. I ended up using a 45* npt elbow. Works great. I can post a picture later. __________________ 1967 Chevy SWB 250 http://67-72chevytrucks.com/vboard/s...d.php?t=442157 1977 Chevy SWB 454 No More 454 getting 5.3 http://67-72chevytrucks.com/vboard/s...d.php?t=310518 1977 Stepside Truck of the month winner http://67-72chevytrucks.com/vboard/s...d.php?t=135524 1965 Chevy C10 454 http://67-72chevytrucks.com/vboard/s...d.php?t=731372 1975 Dodge Power Wagon http://67-72chevytrucks.com/vboard/s...=1#post7871388

07-12-2011, 06:07 PM	#8
justpball Registered User Join Date: Dec 2008 Location: Silverhill, Al Posts: 2,026	Re: Big Block Bypass Hose I blocked mine off with a plug, it still stays cool, so what is it's purpose? Posted via Mobile Device __________________ Fuzzy Dice Club Member 87 Crew SWB Build for the crew http://67-72chevytrucks.com/vboard/s...d.php?t=430082 http://www.cardomain.com/ride/3232925 90 burb 2wd Build Thread For The Burb! http://67-72chevytrucks.com/vboard/s...d.php?t=383055

07-12-2011, 07:24 PM	#9
Grande Rojo paper or plastic? Join Date: Nov 2002 Location: SW Missouri Posts: 671	Re: Big Block Bypass Hose It's a 45* street elbow male end screws into intake manifold and the female end faces down with a threaded nipple for the short hose to the pump. Only cost a few bucks and no kinks. I'm sure it could be smoothed out a little more and painted nice. (I tried posting a picture but my Damn not so smart phone wont let me. I'll try from my home 'puter) Posted via Mobile Device __________________ 1967 Chevy SWB 250 http://67-72chevytrucks.com/vboard/s...d.php?t=442157 1977 Chevy SWB 454 No More 454 getting 5.3 http://67-72chevytrucks.com/vboard/s...d.php?t=310518 1977 Stepside Truck of the month winner http://67-72chevytrucks.com/vboard/s...d.php?t=135524 1965 Chevy C10 454 http://67-72chevytrucks.com/vboard/s...d.php?t=731372 1975 Dodge Power Wagon http://67-72chevytrucks.com/vboard/s...=1#post7871388

07-12-2011, 12:29 PM	#2
kelsfine69 18 Till I Die Join Date: Mar 2005 Location: Alberta, Canada Posts: 1,522	Re: Big Block Bypass Hose I was looking at getting one of these but havet fiqured out which one I need yet. http://www.coolflex.com/cfm/store.cf...t=3&mode=parts __________________ 2011 GMC Acadia 1969 GMC BBC LS7 2007 GMC Crew Duramax 1987 Camaro Iroc 350 Tuned Port Injection 42000Km 1987 Chevrolet Silverado 350 TBI 1987 Chevrolet Silverado 350 TBI(yes 2) Take me drunk, I'm too home...

07-12-2011, 04:12 PM	#6
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose I'd like to see that NPT pic. Is the elbow threaded on both ends, so you thread one end into the water pump and attach the hose to the other threaded end of the nipple?

07-12-2011, 05:14 PM	#7
baclay9 Registered User Join Date: Apr 2010 Location: Newcastle, OK Posts: 1,344	Re: Big Block Bypass Hose I'd like to see something better too, my hose is kinked a little and it is driving me crazy.

07-12-2011, 07:49 PM	#10
raceman6135 Dino burner Join Date: Nov 2002 Location: Calgary, Alberta, Canada Posts: 602	Re: Big Block Bypass Hose Try these molded hoses: Dayco #70647 Gates #20618 Goodyear #63394 They should all look like this:

07-12-2011, 08:12 PM	#11
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose Thanks for the part numbers. All of them show that they do not fit my 83 C20 when I look them up online, but like Keith says I think they should work anyway. I am interested to see what the LMC hose looks like when I get it. I bet even the OEM stock hoses require some cutting to get it to fit. The similar GM OEM short hose from the air cleaner to the valve cover vent hose I paid big $$ for (and looked similar) required modification when I got it.

07-12-2011, 09:24 PM	#12
Metalspatter Registered User Join Date: Jun 2011 Location: Tempe, Arizona Posts: 58	Re: Big Block Bypass Hose I have replaced mine twice now from pulling the intake so many times. Both times I just look through the NAPA hose wall, pick one with the correct bend molded into it, and cut the rest away. Works perfectly and costs only a couple dollars.

07-12-2011, 10:49 PM	#13
KQQL IT At the body shop. Join Date: Aug 2009 Location: Land of fruits and nuts. Posts: 5,202	Re: Big Block Bypass Hose I used a piece of blue silicone hose. Bent without kinking. Posted via Mobile Device __________________ " That didnt make it any newer " " Dont antique the equipment "

07-13-2011, 12:21 AM	#14
78maliburat Registered User Join Date: Jul 2009 Location: cleburne texas Posts: 174	Re: Big Block Bypass Hose MINES A TALL DECK I USED STRAIGHT HOSE

07-13-2011, 12:37 AM	#15
Corts60 Just here to tinker Join Date: Jun 2008 Location: Holland, MI Posts: 3,689	Re: Big Block Bypass Hose Just go to your local parts store and ask to check out the molded hoses. Pick the one that has the right degree elbow (even if it is way too long) take it home and cut it to fit. __________________ 78 C10 SWB Diesel #1 (wrecked)http://67-72chevytrucks.com/vboard/s...1978+silverado 78 C10 SWB Diesel #2 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=650751 60 GMC Suburban (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=445526 60 GMC 1000 (sold)http://67-72chevytrucks.com/vboard/s...d.php?t=298235 67 GMC 1500 (sold) http://67-72chevytrucks.com/vboard/s...d.php?t=803695 86 Suburban(summer unit) http://67-72chevytrucks.com/vboard/s...d.php?t=810697 88 Suburban 4x4(winter unit)https://67-72chevytrucks.com/vboard/...25#post8900725

07-20-2011, 12:25 AM	#17
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose I just got my long awaited correct bypass hose from LMC. Looks like I spent $13 for nothing - somebody just cut a length of 3/4" heater hose off a reel and sent it to me. Probably not worth my additional shipping cost back to LMC + my original $13 to prove a point, but what a disappointment from this vendor. Yet another item to add to my list of minor irritations relating to people no longer taking any pride in their work. I wouldn't mind if they didn't cost me money. Looks like I will have to try one of those "incorrect" correct bypass hoses mentioned previously. Attached Images



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07-20-2011, 07:56 AM	#18
maskale Registered User Join Date: Jul 2011 Location: Houston, Tx Posts: 159	Re: Big Block Bypass Hose that sucks, I would send them some hate mail, make them refund ur money and keep the hose.

07-20-2011, 02:12 PM	#19
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose LMC says they will refund the purchase price including shipping, and don't need the 6" piece of heater hose returned to them. It took about 20 minutes of holding/talking with customer service/check with supervisor, etc. I was told another customer already complained about getting a 6" piece of hose instead of a molded hose. I don't know why they are still allowing customers to order this part. I wonder when/if I see the credit show up in my account? I ordered the two water pump fittings and a molded bypass hose from Corvette Central based on the way the parts look in their online catalog. I am anxious to see what I get for my $38, and if my truck runs faster (like a Corvette) after install.

07-20-2011, 10:07 PM	#20
maskale Registered User Join Date: Jul 2011 Location: Houston, Tx Posts: 159	Re: Big Block Bypass Hose Like I said I went to napa and picked a hose that looked like it will work. I bought it several weeks ago, installed it tonight. Advice, cut just a little at a time, and actually put it on to test the fit vs holding it next to where it goes, I cut mine borderline to short, but it will work for now cost 12.99 IIRC, part number shown on hose

07-20-2011, 10:30 PM	#21
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose Thanks for the tip. I will have to take a picture into the local NAPA store to show them what a bypass hose looks like, since they claim they don't have any and their online store says they have it. Looks like this one has multiple bend angle options for maximum flexibility. https://www.napaonline.com/Catalog/C...267473288&An=0

07-25-2011, 05:14 PM	#22
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose I got my Corvette Central bypass hose and two water pump fittings today. I only took 4 days over the weekend to get the parts via USPS priority mail. The 20 degree angle water pump fitting is supposed to be for 59-62 Corvette, the other fitting is supposed to be for 65-74 big block engines, and the bypass hose is supposed to be for 66-67 big block 427 engines. So, I guess my 83 big block 454 covers many generations of Corvettes. $38 for the 3 parts, including shipping, and the Delco water pump was only $34. I hope these parts do the job. Pics. Attached Images

07-26-2011, 03:31 PM	#23
tucsonjwt Registered User Join Date: Jul 2007 Location: Tucson, AZ Posts: 3,188	Re: Big Block Bypass Hose Installed Corvette water pump fittings and bypass hose with no kink. I cut about 1" off both ends of the hose. Attached Images

07-26-2011, 03:58 PM	#24
maskale Registered User Join Date: Jul 2011 Location: Houston, Tx Posts: 159	Re: Big Block Bypass Hose good ya got it worked out.

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