• The Roadster Factory Recovery Fund - Friends, as you may have heard, The Roadster Factory, a respected British Car Parts business in PA, suffered a total loss in a fire on Christmas Day. Read about it, discuss or ask questions >> HERE. The Triumph Register of America is sponsoring a fund raiser to help TRF get back on their feet. If you can help, vist >> their GoFundMe page.
  • Hey there Guest!
    If you enjoy BCF and find our forum a useful resource, if you appreciate not having ads pop up all over the place and you want to ensure we can stay online - Please consider supporting with an "optional" low-cost annual subscription.
    **Upgrade Now**
    (PS: Subscribers don't see this UGLY banner)
Tips
Tips

Weeping Core Plugs

ian_h

Freshman Member
Country flag
Offline
Hi
I have a couple of weeping core plugs on by 100M
Have changed a couple of times over the years (new core plug put i place and hit in centre with round headed hammer) but they don't seem to seal properly.
Does anyone have a better method or magic sealant I could try?

I believe you can also get rubber plugs which tighten with a screw. Does anyone have experience of these?

Many thanks
Ian
 
Country flag
Offline
Historically, you'd smear some Permatex around the perimeter & put them in. Nowadays, I use Loctite 518.

IMG_1035.jpg


IMG_1036.jpg
 

Michael Oritt

Yoda
Gold
Country flag
Offline
Ian--

I would not recommend using the rubber plugs and I regard them as temporary fixes. Dorman and others make a two-piece all-metal plug which tightens via a nut on a stud that expands the cup. Simply for esthetic reasons I would not use them on my Healey but do on the MGA race engine of my Elva Courier and bed it in JB Weld after carefully cleaning the shoulder, etc. of the hole. I have never had one come out.
 

CraigC

Jedi Trainee
Country flag
Offline
Hi
(new core plug put i place and hit in centre with round headed hammer)

This right here is your problem. I don't care how many different places you have read it or heard it, it is WRONG!
I was shown the correct way 40+ years ago by the machinist who prepped my 100 block during a rebuild. The dish-type plugs seal and hold in place by generating outward pressure while being nearly flattened. The proper tool will leave a slightly concave center in spite of the tool being essentially flat. This is probably where the incorrect method came from.
Go to this page https://www.hubbardspring.com/product/expansion-plugs-brass/ and then click on "installation instructions". There you will find the image below.

welch-plugs-installation-recommendations.jpg
You will see that the tool is flat with a slightly dropped center. This will create considerably more outward pressure to secure the plug. My 100 is good testimony to that. Never lost a core plug and never had weeping from the perimeter. Old age and corrosion did them in. They were replaced last year with brass. If they ever need replacing again it wont be by me. I dont expect to be around another 42 years.

As a distant second to the correct tool, one could use a socket of nearly the diameter of the plug. Turn it around so the back of socket faces the plug. Using a (sacrificial) extension(make sure it does not protrude past the back of socket) strike the plug until it is close to flat around the perimeter. No need to get carried away, you don't want to break the block!

As always, a little sealer in the block cavity for good measure. I always used the Permatex red liquid sealant on core plugs, both to seal the perimeter and coat the surface exposed to coolant.
 
Country flag
Offline
+1, as evidenced by the UHMW "tool" I have in my hand, along with the sealant and core plug. I like the way it dampens the blow__and leaves no tool marks whatsoever.
 
OP
I

ian_h

Freshman Member
Country flag
Offline
Excellent many thanks for the insights
what is the best way to remove the old plugs?
i guess you could drill small hole in centre and insert self tapping screw and then lever out but not keen to get swarf in the block?
ian
 
Country flag
Offline
They're usually weakened from the backsides corroding, so you can drive a screwdriver into them and lever 'em out. I'm typically sending the block/head to be hot-tanked anyway, so I don't worry about a little bit of shavings in the water-jackets (if you've seen some of the things I've pulled out of them, you'd know the manufacturer desn't worry about it either...).
 
Similar threads
Thread starter Title Forum Replies Date
G Right-Side Shock Weeping Oil Austin Healey 1
F TR4/4A New to forum - Rebuilt Fuel Pump and weeping float bowl Triumph 9
cmacmillan TR6 75 TR6 Weep hole weeping.... Triumph 2
T TR2/3/3A TR3 weeping at fuel pump, again Triumph 11
rikiwho123 weeping antifreeze from back of head Triumph 4
M Weeping fuel pump fixed Triumph 0
M Weeping fuel pump fix Triumph 41
G Brake Master Reservoir Weeping.......again Triumph 13
1 Has anyone ever heard this tip? "Weeping" head MG 11
B TR6 Heater core Triumph 0
A Land Rover V8 3.9L long block core for sale Rover / Land Rover 1
HighAltitudeTR3 T-Series Why are there nuts in my core plugs?! MG 8
C Testing heater core Austin Healey 9
RAC68 Radiator Core Replacement and Sleeve Thermostat Alternatives Austin Healey 20
T TR4/4A Core Plug - Cam Rear change Triumph 7
HighAltitudeTR3 Wanted Heater Core, Capping Trim, OD switch 1959 TR3 Triumph Classifieds 3
R TR2/3/3A Heater Core Triumph 2
R Radiator Heater Core Austin Healey 12
steveg Core plug sizes and quantities needed for rebuild Austin Healey 4
S TR2/3/3A heater core Triumph 4
D Recommendation for new core in original 1967 Austin Healey radiator Austin Healey 5
HealeyRick BJ7 Water Pump Core Austin Healey 0
Jake Healey 100 heater core size? Austin Healey 1
AngliaGT 11/73 Midget MKIII - Heater Core Foam Thickness? Spridgets 10
AngliaGT Heater/Heater Core..........Durrrr! Spridgets 8
pbraun Anyone have a 1275 core for rebuilding? Spridgets 8
Got_All_4 Wedge Heater core leak. What am i in for? Triumph 3
M 1275 core Spridgets 15
Got_All_4 A type core Triumph 12
DanLewis Distance between mechanical fan and radiator core Spridgets 17
AN5Sprite Anybody Have A Bugeye Fuel Gauge Core To Spare? Spridgets 3
B TR6 TR6 Heater core plugged? Triumph 9
Pythias Heater Core Replacement Spridgets 7
bugedd Lock core removal Spridgets 12
D 85 XJ6 Heater Core Replacement Advice Wanted Jaguar 19
PAUL161 Moss, New Carb Core Charge? MG 2
George Zeck Heater Core & Battery ...... Spridgets 5
K 1500 Missing CORE PLUG at back of cam isit normal? Triumph 5
M 1098 engine core-need it ? Spridgets 10
G BJ8 Fuel Gauge Core Austin Healey 9
mikecyc72usa MGB 71 MGB ignition lock core removal MG 3
drambuie How many more core's can a stock radiator handle Austin Healey 8
Luke_Healey Cheap options for a heater core? Spridgets 11
luke44 TR2/3/3A TR3 Water Temp Gauge Core Triumph 14
J Core plugs/freeze plugs Austin Healey 7
mgbmedic Wedge 1980 TR7 Heater Core Triumph 2
B MGB Dashboard Core 71 mgb MG 10
H Core plugs Austin Healey 3
H Replacing Core plugs Austin Healey 1
Morris Solid core wire Spridgets 6

Similar threads

Top