Radiator cap - cars that DON'T take the later cap.

Post by **billofdurham** » 12 Jan 2009, 11:44

This post is to be read in conjunction with "Update your Radiator Cap! 2/7/9/series."

The following models, year and engine designation DO NOT take the later cap which is rated at 1.5bar. Using the later cap WILL cause damage to these cars.

240.

B200K '84 - '89 0.75 - 0.85bar
B230A '84 - '88 0.65 - 0.85bar

740.

B200K '84 - '89 1.0bar
B200E '88 - '89 0.75bar
B200F '89 - '92 1.0bar
B230K '84 - '86 1.0bar
B230E '84 - '89 1.0bar
B230F '86 - '91 1.0bar

940.

B200F '91 - '95 1.0bar

Bill.

girlbunny · Post by **girlbunny** » 13 Jan 2009, 16:20

How do I know if my 940 is the one listed or not? I have a 1990 940 16 Valve automatic sedan. From memory was released in late 1990 and is officially called a 1991 version.

Thanks

Post by **MadeInJapan** » 13 Jan 2009, 16:33

Check it against the list here: https://www.matthewsvolvosite.com/forums ... f=2&t=9943
Bill has only listed those that should not upgrade to the new cap in the thread here.

Post by **billofdurham** » 15 Jan 2009, 12:33

I have a 1990 940 16 Valve automatic sedan. From memory was released in late 1990 and is officially called a 1991 version.

This is a problem caused by Volvo and other manufacturers releasing the next year's models in the last three months of the preceding year. Although your car was on the road in 1990 none of my Volvo 940 repair, history nor data books show anything before the 1991 model.

However, all 940 B234F engined 940s have a radiator cap rated at 1.5 bar.

Bill.

girlbunny · Post by **girlbunny** » 16 Jan 2009, 01:19

So I guess mine's a B234F engine? Either way at 1.5bar, it can take the different cap

Much appreciated

Post by **billofdurham** » 16 Jan 2009, 12:42

Indeed it is and it is an 'interference' engine. The timing belt must be changed every 50,000 miles. If it snaps your engine will require much work if it is even possible to repair it.

Bill.

Post by **egads** » 31 Jan 2010, 01:36

Hi, I am a little confused and want to get this right as my rad has just burst and my car isn't listed. It is a 1985 240GL with a B230E engine with K-Jet. Should I go off the 740 for the cap (don't update) or is it different with a 240?
Thanks in advance.

William

Post by **billofdurham** » 31 Jan 2010, 16:01

Sorry I missed that one for the 240.

The '85 B230E 240 takes the 0.85bar cap.

Bill.

waydar · Post by **waydar** » 18 Oct 2010, 19:51

Can you explain why the 1.5 bar cap will damage the engines on your list? Thx., Wayne

Post by **billofdurham** » 30 Nov 2010, 12:21

I missed this one,sorry.

The engines listed are designed to run at lower pressure. Using the green cap will increase the pressure, in some cases to double that recommended. A high-pressure radiator cap puts greater stress on the rest of the system (clamps, hoses, gasket surfaces, and so on).

Raising your radiator cap's pressure above factory specs increases your cooling system's maximum operating pressure above design parameters. While raising your cooling system's maximum operating pressure does raise it's boiling point and, therefore, helps to avoid boil-over, it does not lower your operating temperature prior to boil-over, and simply allows your engine to continue to operate at temperatures higher than it is engineered for. Water boils at 212 degrees, and for each pound you raise the system pressure it raises the boiling point 3 degrees - Example: The 0.75 bar (11 psi) cap will have a boiling point of 245 degrees. The 15 bar (21) psi cap will push the boiling point to 275 degrees. Operating an engine at higher than acceptable temperatures can destroy it.

Bill.