So quick question and trying to sift through all the posts over the last 20 years and couldn't find the answer...

Have 400 SBC running Hooker long tubes, not enough room for the knock sensor on the passenger side... other option is to move above the oil filter on drivers side... are the two locations the same thread size? Currently on mine, above the oil filter, its a blind hole/boss with threads but the knock sensor I got does not thread in.

TIA for any help!

 

I kinda don't think so.

The knock sensor is ¼" pipe. You can go to the parts store and check an oil pressure sending unit that's for that hole and see if it's that size. Butt I think it's something larger; 3/8" pipe maybe. You could probably use a bushing if it is.

That hole is not "blind". It's the end of an oil passage that the factory drilled and then used that plug to seal off.

 

I'm no expert on 400 SBC blocks. I know there are 2 and 4 bolt main versions and 3 core plug and 2 core plug blocks. I know on the SBC engines that came in our cars that the knock sensor screws into the passenger side lower block drain and on the driver side of the block is the same lower block drain with a plug screwed into it.

IDK if the 400 SBC block also has a driver side block drain too. IDK how the headers you have are routed on the driver side. If you have a driver side block drain and the headers provide enough clearance on the driver's side maybe you can relocate it there.

 

https://www.jegs.com/i/Ron-Francis-W...tent=Evergreen

 

It mos def does. The 400 is the same as any other block, SBC or any other, in that regard. How else would it be possible to drain it?

I'm having a real hard time imagining how headers can interfere with the pass side drain plug location. Can't see how that would be possible, and still clear the starter and engine mount.

 

Not sure what the interference might be, but the 01-07 L31 350 powered trucks built on the GMT800 platform used 4 bolt LS mounts on the block and the engine mount interfered with the knock sensor connector. GM put a knock sensor on those trucks that has a connector on a length of wire away from the sensor. The L31 knock sensor is the same sensor as a mass air TPI.

 

So this was my issue also. I ended up screwing a fitting into the block that did a 90. Then screwed the knock sensor into the fitting. Some say this slightly reduces the sensitivity of the sensor. I've never had any issues.

 

That's one FUNKY header primary routing.

If the OP's situation is similar then the same solution should work fine.

 

Hooker 2210's. Besides the knock sensor I had no other issues with them which was nice.

 

Yeah just looks like it could have been routed outward so that it was more tucked in together with the others. Butt as we all know there's often more to the story than can be seen in one pic.

 

Thanks for the responses. Running the same headers as well so you see my concern. Drivers side would be a great option but I am not using the drivers side drain plug because it is seized.

Since you have had luck with adding a 90 in there, that may be the way to go for now and if there is an issue later down the road then I can turn back and look at the passenger side again.

Thanks again, guys!

 

Heat it....it will come out. I'd get that thing out while you have access to it; need it to come out to drain/fluch coolant, anyway, as Sofa mentioned.

 

Heat and candle wax is a trick I have used. Heat it up, then stick a candle to it.

 

Or just heat it. Candle f'ing wax....the move of the desperate. Try dog **** too. And Fabreeze...I heard that works! Or pray? Maybe? I can't help but wonder: How many guys here (besides Fast) have a candle in their tool box? Or in their garage? Or even anywhere on their property???

No, just heat it. Heat works. If you heat it up HOT, it'll come right on out of there. And not in 4 days (of soaking), not after a trip to the grocery store to buy...f'ing CANDLES!! , not after wasting time w/potions, elixirs and hope, dreams & prayers....Nope...heat it up HOT, and it'll come out RIGHT NOW. How do I know? I've been a mechanic, and the boss of mechanics for over 30 years. Extracted 100's of "frozen" bolts w/HEAT....never dick'd around w/candle wax. Never needed to, and never will. Waste of time ....and candles.

HEAT WORKS

 

Laugh all you want. Pipe plugs are one place where heat itself is sometimes not enough especially when the plugs are made of two different materials. Like it or not heat and wax is a proven method. It was a tip I learned from a machine shop owner who had been in business for 40+ years.

https://youtu.be/wDoHN7KZzaI?si=diH5rrDsCILR73ly

 

O.K. I'll have a laugh at this: Which candle works the best? Yankee Candles? Bath & Body Works' candles? Brooklyn Candle Studios' candles? And...Fast, what candle scent works the best, on stuck bolts?? Pine Forest? Sparkling Cinnamon? Is Balsam & Cedar scent, the best "rust BUSTER"??
And....Holycrap! A YT vid from "motion24527" (whoever the f THAT is)!? WOW...I'm SOLD on candle wax now!! O.K. That's enough laughs.

No...no laughing here....posts like ^that^ are more of a disappointment, than laughable. You have told yourself a fallacy. The heat got your pipe plugs out. You applied your own, special "religion"....and then applied the credit to that. "I prayed to Allah this morning, and my car STARTED! Allah got my car started!! No. The battery, ignition switch, key, wiring, starter motor, etc. etc. started the car. Praying to Allah (the "candle wax") had nothing to do with the car starting. Can you see the failure of that line of "reasoning"?

And that's fine. Religion/make up stories all you want, if it makes you feel special. But don't waste the time of the unwitting by giving out bad "advice" on forums! No, wax don't get rusted fasteners out/off. HEAT DOES. I'm no "motion24527" yootoober, but in the link that *I* posted, I got bolts out that were WAY more rusted than his was...and somehow, I did it w/o Candles! How?? I AM the "machine shop owner who had been in business for 40+ years". This is my lively hood; get **** fixed and teaching/showing my techs how to get it done. I don't want 'em driving to the CANDLE STORE, I want them producing.....and since I'm salaried, the faster I can get something done, or show how it's done, the sooner I can go home. So? I HEAT the F-out of it and get it apart. RIGHT NOW.

 

I've always preferred the pine scented candles. Much faster bolt release and better than cinnamon. I use wax on all my bolt threads too (heads, exhaust, intake, ALL of them), that way the wax is already there when I need it later. Thinking about just getting a huge blob of wax and blowtorching it all over my engine. Pine scent of course.

 

Mmmmm....those are some compelling point you have made, Aaron. I admit that I have never tried the basic Pine scented candles. Perhaps I should give the candle-wax-tool, more thought?

I embarked on some "extensive internet research" and found that in fact, there is quite a following for the Pine scented candle bolt remover! From the yoo-toob vids I watched of hicks-in-garages-trying-to-look-smart, it seems that the Cherry scented candles don't have enough bolt-extracting power to pull itself through a wet paper bag. But the Pine scent....oh boy, that's a WHOLE different....ball of wax! The pine scent, it seems, blows past the other scents on the top-end....I mean...I mean, at getting bolts out!

 

TLDW it didn't work

 

It's been my experience that heat is the only thing that will loosen a rusted pipe plug or nut/bolt; the expansion and subsequent contraction will almost always break the bond and allow the part to be removed. While I've heard of the 'candle wax' deal in the past, I've never tried it myself; I never needed to.

 

I have had to use candle wax to get an iron plug out of an aluminum manifold. Heat alone did not work. Penetrating oil did not work. I had the plug glowing orange several times. Tried the candle wax on it, came right out. You apply the wax when the plug is practically still glowing and it does help remove said plug. The other instances I have had heat alone not work is exhaust hardware and GM upper control arm nuts.

 

Not nearly enough heat. Need a MAP gas torch at a minimum preferably an OxyAcetelyne.

 

Thanks, but at this point it's not "easily" accessible. Sitting half way in the garage with the front end jacked up enough get under and do what I need to do.

Honestly I believe it's a moot point at this time to fix it. Just want to get it running again and get it to paint an body. Come to think of it not really sure why I am adding the sensor in since I ran a Haltech E6GM before without the sensor and then swapped to the EBL P4 in 2017 but when I swapped to the EBL I got it running and drivable around the block then parked it to swap from the 89 harness to a 91 harness since the 89 was hacked up to hell and back and I didn't make matters any better . That was back in 2017.

Block is obviously old being a 400, came out of 71 Impala I think it was, but found it leaning up against a tree way back in 1999 or 2000, had block bored first to see how bad it was.. lol.. shop had to go 60 over. So yeah it's on it's last leg, but right not it's more important is to get it running, get it looking pretty again, and enjoy it till I can blow the motor for an LSx swap.

And loved the explanation between candle wax and religion, so true and gave me and the Wife a good chuckle!

 

 

Haven't had a knock sensor in my 89 since the early 90s 350 combos. Went to a 400 block not long after that. Stock tpi ecm

 

Another option, and it's worked for me more than once: