Loctite, which one?

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DaveRC

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Loctite, which one ??? just can't work out what I need ???

I need to loctite in some valve guides, bronze into aluminium.

I see people on here use Loctite for all sorts, I have never used it before, what do I get and how do you use it?

Thanks

Dave
 
DaveRC said:
Loctite, which one ??? just can't work out what I need ???

I need to loctite in some valve guides, bronze into aluminium.

I see people on here use Loctite for all sorts, I have never used it before, what do I get and how do you use it?

Thanks

Dave

Dave, their are quite a few Loctite numbers that could work. But, If your parts span between a press fit and up to .005" gap, then I recommend #609. It has the correct viscosity to coat the surfaces properly. And its makes for a very strong joint. Its the one I use on all my work.

To use Loctite its important to degrease both parts with lacquer thinner (or equivalent) , coat both parts on their mating surfaces and install a with a one direction twist, or press them together quickly in one motion if the gap is a press fit. The closer the gap, the quicker it sets up. In the case of a press fit their will be no time to make any adjustments. You got to get it right on the first try.

-MB
 
609 will probably be fine in a model engine, but if you expect the head to get hot you should consider the high temperature retaining compound, #620.
 
Sleeve retainer. Both Loctite and Permatex make a version. They are specifically made for things like bonding piston sleeves and valve guides.
The Loctite number is 620 Retaining Compound.
The Permatex kind is just called High Temperature Sleeve Retainer.
 
I withdraw my suggestion of using Loctite # 609 to secure valve guides on an I.C. engine. :wall:

Deanofid and dieselpilot are correct with their recommendation.

I checked on the temperature ratings and Loctite #609 is rated at only 300 degrees Fahrenheit.

And the #620 is rated at 450-F.

-MB
 
Thanks guys, good information as usual, now hunting for 620, any clues where to get this stuff. Have had a hunt on the net and it only seems to be in 250ml bottles (at over £100 :eek: ) can't seem to fin small bottles of the stuff...

Dave
 
Hi,

Just can't find the Loctite 620 at any reasonable price, can find Loctite 648, which seems to have very similar properties, only major difference I can see is the temperature range, max temp on the 648 is 175C or 347F, is this high enough for valve guides on an air cooled 4 stroke...?

Dave
 
DaveRC said:
Hi,

Just can't find the Loctite 620 at any reasonable price, can find Loctite 648, which seems to have very similar properties, only major difference I can see is the temperature range, max temp on the 648 is 175C or 347F, is this high enough for valve guides on an air cooled 4 stroke...?

Dave

Its very pricey stuff that #620. You cold use the Permatex equivalent called 'Sleeve retainer'.

Here's another option if you would like to buy a smaller lower cost amount. You could get on the phone to check price and availability at your nearest auto parts stores that stock Permatex products.

http://www.google.com/products/cata...og_result&ct=result&resnum=5&ved=0CDYQ8wIwBA#

-MB
 
I would highly recommend getting Carroll Smith's book "Nuts, Bolts, Fasteners and Plumbing" as it's an interesting read about all fasteners but specifically he talks about a few of the Loctite verities and when/where to use them.

This is the google book result for the section on Loctite:
http://books.google.com/books?id=A81HmmRCN7YC&pg=PA129&lpg=PA129&dq=carroll+smith+loctite&source=bl&ots=ZvrJAICFQz&sig=1MssJZ4y3M5qAZNNVWwTD5RF45M&hl=en&ei=6fRGTe_NBo6ksQOHt5WOCg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBsQ6AEwAA#v=onepage&q&f=false
 
Looking at the Loctite website they list the 620 in three sizes. 10ml, 50ml, and 250ml. Finding a supplier in the UK is an unknown to me. But it is available in the USA according to the site. Here is the pdf about the various Loctite Retaining Solutions Guide:
http://useloctite.com/filephotos/documents/Retaining_Solutions_Guide.pdf

EDIT
One possible lead is Grainger Company's representative for the UK:
REP NAME PHONE EMAIL REGION
Lee Pruitt 44 774 957 5046 [email protected] Europe

Grainger does list the various sizes in their catalog and do export to the UK:
http://www.grainger.com/Grainger/wwg/search.shtml?searchQuery=loctite+620&op=search&Ntt=loctite+620&N=0&sst=All
 
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