What helicoil thread sizes best to keep on hand for automotive?
#1
What helicoil thread sizes best to keep on hand for automotive?
I need to get some Helicoils to keep on standby for automotive thread repair. It's too expensive to buy a bunch of different sizes. What are a few of the more common standard thread sizes I would see on 92' Ford Ranger? Would 1/4-20 be one?
Top Answer
11-12-19, 01:40 PM
Group Moderator
I've still got the Helicoils I bought 30 years ago. I just don't have much need for them. When you need one you need one but it's not a commonly used item. Certainly not used often enough to just buy to keep in stock.
#2
Forum Topic Moderator
I've only used heli coils a handful of times. IMO that doesn't warrant stocking them in your home shop. I would suggest getting [if you don't already have one] a tap and die set so you can chase threads - that's something I use fairly often.
Furd
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#3
Group Moderator
I've still got the Helicoils I bought 30 years ago. I just don't have much need for them. When you need one you need one but it's not a commonly used item. Certainly not used often enough to just buy to keep in stock.
Furd,
joecaption
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#5
Member
Echoing what has already been said, I think I have a couple in one of my boxes, only because I probably used one out of a package, but that would have been 30 or more years ago, and I have not found a use for one since. Nothing against the company because they do work, and might even seem somewhat intriguing, but the reality is that there are generally better solutions. As Mark said, put the money toward a tap and die set, and I would add a set of thread files. More often than not a jimmied thread can be salvaged, or, if not, a lot of times you have room to simply drill and tap to the next size. My opinion, investing in a set or even quantities of select sizes is skirting better options and inviting problems down the road.
#6
Hmm..........Well, I'm glad I asked you guys. I do have a thread tapping kit for standard. I asked because I have a stripped transmission filter mounting bolt hole that won't last another fluid change. I've been nursing it along for a few years.
I also have a couple trans fluid pan bolt holes that are stripping. I've been scraping by with 'Mr Grip' thread repair strips. But can't tighten very well with those.
You definitely got my attention with the thread chaser and thread file suggestions. Are these items carried by the usual brick and mortar hardware chains?
I also have a couple trans fluid pan bolt holes that are stripping. I've been scraping by with 'Mr Grip' thread repair strips. But can't tighten very well with those.
You definitely got my attention with the thread chaser and thread file suggestions. Are these items carried by the usual brick and mortar hardware chains?
Last edited by bluesbreaker; 11-12-19 at 08:20 PM.
#7
I do have a thread tapping kit for standard
joecaption
voted this post useful.
#8
Forum Topic Moderator
My first tap and die set was a cheap one from Harbor Freight. Long ago I replaced it with 2 Craftsman sets [metric & SAE] A cheap set is adequate for chasing threads but you need a better set to cut new threads. Most any store that sells an assortment of tools sells them. I prefer the type that has the octagon shaped dies rather than the old round ones.
#9
This is true. I have noticed metric threads on my 92' Ranger. Yeah, I noticed Craftsman/Snap-On/Kastar seems to be the popular thread chaser kit online.
Can you tap new threads in bolt holes, from metric to standard and vice versa?
Can you tap new threads in bolt holes, from metric to standard and vice versa?
#10
Forum Topic Moderator
You can tap a completely new thread providing most/all of the old thread is gone and you have a decent tap/die set. The el cheapo tap and die sets struggle to cut completely new thread.
#11
I'm kinda' confused at the difference between 'thread chaser' and thread tap tool. The two terms seem to be interchangeable at times. I looked at the Craftsman thread restorer kit. I see what appears to be thread chasers. But the description just calls it 'tap.'
Can you attach a picture of a 'thread chaser' and a kit part number? I don't want to buy the wrong product.
Can you attach a picture of a 'thread chaser' and a kit part number? I don't want to buy the wrong product.
Last edited by bluesbreaker; 11-13-19 at 08:00 AM.
#12
Forum Topic Moderator
I've always used a tap and die set to chase threads [basically cleaning/aligning them] Any tap and die set is suitable for that. Only the better sets are good for cutting new threads.
#13
I attached two photos from online. The silvery looking ones with 'barrels' are called thread chasers. The narrower black and silver ones are called thread taps.
Any difference? Do I need both designs?
Any difference? Do I need both designs?
#14
Member
By design and intent, the purpose of a tap is to create a threaded hole where one did not exist, and the purpose of a chaser is to clean up an already threaded hole. If you compare the ends of a die and chaser, you will see that the die starts smaller diameter with flatter lead threads, which help align it and allow it to gradually cut away the metal to cut the thread, whereas the lead threads on a chaser more closely resemble the actual threads, and are not tapered as much because you want it to follow the threads that are already there. Consequently, I can't say that I've ever tried, but am quite certain that you cannot create new threads with a chaser. On the other hand, you can chase threads with a tap, but you need to be careful that you start it exactly in synch with the existing threads, lest you end up reconfiguring the original threads, which is going to leave you with a sloppy fit. For chasers, the threads are already there, so you match the chaser to what you have. As far as your earlier question about rethreading an existing metric thread to US, or vice versa, each tap requires a specific size pilot hole, often stamped on the shank of the die, so unless you can drill the hole out to that size first I would not recommend it because here again you will end up with a sloppy, and most likely unacceptable, fit.
#15
Member
I have to 100% agree with these post, in 50 plus years of working in machine repair, and owning a ton of equipment I may have used an insert twice.
Depending on the year and your where truck was made often times as pointed out it will be metric.
Most I've seen where made by Mazda or in Canada.
All the auto stores in my area have repair kits for oil pan and transmission pans that includes a drill, insert, and new bolt and gasket.
Depending on the year and your where truck was made often times as pointed out it will be metric.
Most I've seen where made by Mazda or in Canada.
All the auto stores in my area have repair kits for oil pan and transmission pans that includes a drill, insert, and new bolt and gasket.
#16
Thanks. Very informative. I agree that it is not worth investing in helicoils. Maybe keep a few on hand. I'm leaning towards getting a good metric/SAE combo thread tap instead of chaser.
#17
I'm going to buy Gearwrench part#3887 75 piece SAE/Metric tap and die set. This product has consistent high ratings. We can close out this discussion. Thanks for all your input.