The Triumph Dolomite Club - Discussion Forum

Hello all again!

A little while ago I replaced a tube on top of the engine that was leaking coolant, however now I think I've got a possible leaking bypass tube by the thermostat housing? Coolant keeps gathering in the little groove between the engine block and the housing, and running down beneath the inlet manifold down the side of the engine.

Apparently that the way to fix this involves taking the inlet manifold off but I can't find gaskets outside Rimmers anywhere, but I've heard their gaskets are pretty poor?! Fitchett don't seem to have any, any other recommendations?

Also, as I'm on the subject, my temp gauge usually sits about 2/3 the way up, and on hills can climb right up almost to 3/4? Planning on flushing the system through when I try fix the leak, but is that normal? My last car never went over about 1/4!

Thanks guys

Searched your other posts.......you have an 1850!

Rimmers sell decent inlet manifold gaskets, but you should always check their fit (against the cylinder head ports) and trim if necessary.
You also will need the inlet manifold O-ring.
(You can also buy gasket paper and cut your own gaskets, if you prefer.)

Furthermore, if the inlet manifold is removed, you will need new O-rings for the by-pass tube.

The inlet manifold gaskets and O-ring can fail allowing coolant to seep out.



Other possible sources of the leak you have could be
the water pump cover hosetail (if it is a 6 vane pump, the hosetail has a fibre washer) or the hose itself
the metal pipe (that runs from beside the distributor to the WP cover
the water pump cover bolts.




Ian.

The reading is a bit high but some senders do read higher than others especially if the voltage stabilisor is faulty.
You can get new solid state ones on ebay.

Suspect your bypass tube needs new O rings...and the holes need a good clean of all previous sealants and limescale.

Moss will have a decent inlet manifold gasket but I've made my own from cereal packets...you just need a template,
a scalpel and a hole punch.

Jonners

The reason you may have had problems finding the gaskets is because the part numbers have changed.
The gaskets were GEG671 ( now AJM671 ) and GEG670 ( now AJM670 ). The O-ring sealing the manifold to head was a 157415 ( now TRS2024 ). The O-rings for the bypass tube are TRS1114 Qty 2.
If you still have the early 1-piece variant of the bypass tube where the O-rings are moulded as 1 piece in the bypass tube you will also need UKC2538 Link tube. The TRS1114 rings are then fitted to this.
I've had Rimmers gaskets and seals in the past and they are good.
It is always worth thoroughly cleaning the seating areas of the bypass tube in the water pump housing and the inlet manifold and just using a smear of Hylomar type sealant on the O-rings so they don't get pushed off the tube during installation. I retain the large O-ring in the manifold also with a smear of Hylomar.
Don't overdo the tightening torque on the manifold bolts, they are quite short and only in alloy.
Can you get an electronic thermometer in the thermostat housing to check the temperature ? That would tell you whether it is actually running hot. My 1850 gauge reads 80 deg C at 1/2 way and 92 deg C at the 3/4 mark.
Is the car running on this Evans waterless coolant ? Mine runs hotter due to this as it has a lower specific heat compared with water.
HTH,
Tony.

Sorry about that! Completely forgot to put what I own! :') thanks for your detective work! I'm glad to hear success stories from Rimmers, it will definitely be cheaper to just have the one shipment of parts from them! I'm not sure which pump I have, is there an obvious way to check? I think the metal pipe is ok but it definitely is on its way out.

I've seen somewhere in my paperwork that the voltage stabiliser has been replaced in the last few years, which leads me to believe this has been happening for a while! I don't think its done any harm, everything seems to be running pretty well, I'd love to do a compression test to be sure though. I might look into whipping the thermostat out and checking that too, to see what it thinks of hot water. I've got a spare in the boot and I'm wondering if thats an 82 degree one. I didn't realise you could make gaskets out of cereal packets! And there was me worrying about Rimmers!

Thanks again Tony for your great help, will check up what I have and order accordingly! I'm assuming if I have the early variant of the thermostat housing that means early type of the bypass tube?

Just having looked into Evans coolant, I'm thinking thats what I might have! The coolant has a slight green tint to it which would make sense! However I've just been adding regular glycol coolant to it as top up? I had no idea Evans existed!