| Author | Message | ||
     Mujahid Khan Experienced User Username: anjumkha Post Number: 26 Registered: 12-2003 |
SSII 1977 Finally the heads came back from the shop. The diagnosis was "slight warping" I have gasket etc ready. The manual recommends to apply a sealant to the gasket. But I have read on this forum not to use any thing on the gasket. Please illuminate Best regards M Khan | ||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 1048 Registered: 4-2003 |
Out of interest, what part number is the gasket ? The originals were UE31004, where some Wellseal gasket compound was indeed specified from 1958 to 1982. There are several subsequent part numbers quoted, including the early UE31004, then later RH13109, UT12890, UE45215, UE74798 and finally UE74798. There may even have been others. Commencing with the Turbo cars, gasket compound was deleted, and the practice of fitting the heads dry was later standardised across the V8 range from the S2/SCII vehicles onwards in a service bulletin. I believe that the UT12890 gasket is standardised for all cars between 1958 and 1993 model years. The manual states that no gasket compound should be applied to these gaskets. This has been standard practice for many years now. If your part number is UT12890, RH13109, UE45215, UE74798 or UE74798 then you can safely follow the bulletin and fit it dry. Otherwise watch this space.  (Message edited by Richard Treacy on July 12, 2006) | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 592 Registered: 9-2004 |
Muja,Stop stop stop. It is my suggestion to you that the heads being warped are caused by other factors not found through not doing the correct checks in the first place. If they have distorted by any degree then do check the wet liners and alloy block for faults. This will also show up piston possible probs caused by the overheating. There will also be the reading of the old gaskets for certain signs. Did the weep holes show signs of water or oil? The primary cause could have been running the system without the thermostat or a restricted rad etc. However i have seen many engines recked by folk who do not get to the cause in the first place. It is my opinion that the alloy heads warping are secondary serious faults. | ||
| Mujahid Khan Experienced User Username: anjumkha Post Number: 27 Registered: 12-2003 |
Pat : What are the signs I need to inspect on the old gaskets? Can you guide me on how to accurately read the tell tale signs. Regarsds M Khan | ||
| Patrick Lockyer. Grand Master Username: pat_lockyer Post Number: 593 Registered: 9-2004 |
Muja,look for a varied pressure mark indicating the cylinder or cylinders at fault. Movment of the liner sealing on the gasket face indicating incorrect torque of studs or total blow by of the gasket etc,this can be caused by the continual running of a system that boils. Check the block water ways for ginger staining, this will confirm that air has been able to get into the system, many causes here, early tests stated would have found the real cause. Hope this helps at this late stage. | ||
| bob uk Unregistered guest Posted From: brig-cache-4.server.ntli.net |
Heda gaskets are sometimes coated in a sealant that lookes like varnish. When the engine is running the heat of the engine and the clamping force on the head causes the sealant to activate and seal the head joint. When a cylinder head warps it warps both sides. It does not get thicker and thiner. This means that when the rocker shaft is bolted down to a head that has been skimmed the rocker shaft bends a bit. Because the rocker shaft does not turn providing the warp was small then no problems wil result. heads that have camshaft in them or bolted to them (ohc) are a different matter and can casue the cam to break due to the bending forces of out of line cam bearings. The Shadow has hydraulic cam followers. If the head is skimmed make sure that the followers are still operating in the design range. If the followers are out of range then shims must be fitted under the rocker pedestals to lift the rocker shaft up. Pat is absolutely correct. You must find out why the head gaskets blew in the first place. I always check the radiator carefully. One test I do is to physically remove the radiator and do a guessimate hand weigh of the rad if it feels heavy then it is a sure bet that the rad is clogged. Another test is to fill the rad with water and drain into a bucket to see how much water capacity the rad has. another is to pour boiling water in the rad and feel the rad with your hand to check for cold spots which means blockages. I have had radiators that look good externally but when checked they have cold spots and feel overweight. If in any doubt get the rad recored. The core is of the older gill type. The cores come in various sizes and depths and the reconditioners can cut another size core to fit the bottom and top tanks. In the range of Radiators sizes the shadow rad is not that big and there will be a core that can be used. There is nothing special about the rad. I have noticed that some have a misconception about what the themostat does and how relaiable they are. The stat is important because it also guides the coolant around the system without, the coolant is liable to go the shortest route and go through the bypass when it should not ( engine hot) Stats are very realiable and once a new one is fitted it will last for many years. To test a stat place in saucepan of water bring to a boil and observe the stat it should have openned before the water boiled if you have a thermometer it should start opening about 80 degrees and be fully openned at about 86 degrees. I have found that stats either work or they don't if the stat opens in hot water then most likely it is openning at the correct temperature. Most modern stats fail safe and remain open ( by pass closed ) To test a stat in situ ( engine running and warm)feel the top and bottom hose if the top hose is cold then the stat is shut. The bottom hose should be colder than the top because the rqadiator should be drawing heat out of the water. Infar-red thermometers are very usefull- point and take a reading Water pumps are simple machines and providing the bearings are not slack and quiet and thye are not leaking and the are going round and the belt is not slipping then the pump must pump. that said I did once see a pump where the impellor fell off and it appeared ok but it didn't pump. had me going that one. Also car water pumps are surprising powerful. not so much pressure but the volume of water they can shift. I always suspect radiators when problems like this come up so do check the rad carefully. Also remember that the stat must be fitted. The coolant goes into the top of the rad and comes out of the bottom of the rad and back to the engine. (Message approved by david_gore) |
